Comprehensive Dossier· Cyprus two-state solution guarantor rights explained

The Cyprus Channel: Guarantor Rights, Sovereign Equality and the Two-State Vision

Cyprus two-state solution guarantor rights explained: the 1959–60 treaties, 1974, Annan, Crans-Montana and 2024, with each party's own documents.

COD

By Corridors of Diplomacy Editorial Team

Published: October 27, 2026

⏱ 15 min read (3,073 words)

Executive Summary & Key Facts

The 1960 Treaty of Guarantee gave Türkiye, Greece and the United Kingdom a treaty right under Article IV to act, after consultation, to restore the constitutional order; Ankara cites it as the legal basis of its 20 July 1974 Peace Operation, while Greek Cypriot and many international sources dispute how far it permits force.
In the 24 April 2004 Annan Plan referendums, 64.91% of Turkish Cypriots voted Yes and 75.83% of Greek Cypriots voted No; the Republic of Cyprus joined the EU a week later, on 1 May 2004.
Ankara and the TRNC argue that more than five decades of federation talks (1977/1979 High-Level Agreements, 2004, Crans-Montana 2017, Geneva 2021, New York 2024) show the federal model is exhausted and that talks must begin from sovereign equality and equal international status.
The UN Security Council, the EU, Greece and the Republic of Cyprus continue to rest their positions on a bizonal, bicommunal federation with political equality, and UNSC Resolutions 541 (1983) and 550 (1984) call the TRNC proclamation legally invalid.
Only Türkiye recognizes the TRNC as a state, although the TRNC holds observer status in the Organization of Turkic States and participates in the Organisation of Islamic Cooperation under the designation 'Turkish Cypriot State'.

Why It Matters

The Cyprus issue is a dispute over what a lasting settlement must be built on: a federation negotiated under UN resolutions, or the sovereign equality of two peoples on the island. Ankara and the Turkish Republic of Northern Cyprus (TRNC) argue that the federal model has been exhausted and that any corridor to a settlement must start from the 1959–60 treaty floor, sovereign equality and equal international status. The UN, the EU, Greece and the Republic of Cyprus still anchor their positions in a bizonal, bicommunal federation. This guide sets out both sides from their own documents.

The Cyprus Channel desk treats negotiation as a corridor with a fixed legal floor. That floor is the set of treaties and votes that every party must account for, whichever conclusion they draw from them.

Background

The 1959–60 settlement: a partnership republic

The modern Cyprus question starts with the Zurich Agreement (11 February 1959) and the London Agreement (19 February 1959). Britain had administered the island since 1878, and its administration was recognized in the 1923 Treaty of Lausanne. The agreements followed the Greek Cypriot campaign for ENOSIS (union with Greece) and the armed campaign of EOKA, founded in 1955, which Ankara and Turkish Cypriots describe as a terrorist organization. During 1955–1958 Turkish Cypriots left some 33 mixed villages, according to Turkish sources.

The Republic of Cyprus was established on 16 August 1960 as a partnership state of two communities. Its constitution provided for:

a Greek Cypriot President and a Turkish Cypriot Vice President, each with separate veto powers over foreign affairs, defence and security;
fixed community ratios in the House of Representatives (70:30) and the public service;
three treaties: the Treaty of Establishment (with the UK, which kept the Sovereign Base Areas), the Treaty of Alliance, and the Treaty of Guarantee.

As the treaty text provides, in Article I the Republic undertook to maintain its independence, territorial integrity, security and constitutional order, and to prohibit activity promoting union with any other state or partition of the island. Under Article II, Greece, Türkiye and the UK recognized and guaranteed that state of affairs. Article IV says that, in the event of a breach, the guarantors will consult on measures to ensure observance. Where common or concerted action proves impossible, each guarantor reserves the right to act with the sole aim of re-establishing the state of affairs created by the treaty.

1963–64: the partnership breaks down

On 30 November 1963 Archbishop Makarios put forward 13 proposed constitutional amendments, including curbs on the Vice President's veto. The Turkish Cypriot leadership and Ankara rejected them on 16 December, as Turkish sources record. Greek Cypriot accounts present the proposals as an attempt to make a deadlocked constitution workable. Intercommunal fighting broke out on 21 December 1963 ('Bloody Christmas'). Turkish Cypriot sources say roughly 30,000 people were displaced from 103 villages and that Turkish Cypriots were pushed out of state organs. Nicosia was divided along the Green Line on 30 December 1963. For the detailed sequence, see 21 December 1963 and the Green Line: How the Partnership Republic Broke Down.

UN Security Council Resolution 186 (4 March 1964) recommended the UN peacekeeping force (UNFICYP) and referred to the 'Government of Cyprus'. Ankara argues that this wording treated one community's administration as the government of the whole republic and began a structural status asymmetry. UN practice since then has treated the Republic of Cyprus as the internationally recognized government.

1974: coup, intervention and division

On 15 July 1974 the Greek military junta and Nicos Sampson, a former EOKA gunman, overthrew Makarios. Türkiye, after consulting the UK, launched its Cyprus Peace Operation on 20 July 1974, with a second phase in August. Ankara cites Article IV of the Treaty of Guarantee. Greece, the Republic of Cyprus and many international bodies call the operation an invasion and an occupation. UNSC Resolution 353 (20 July 1974) called for respect for Cyprus's sovereignty and territorial integrity and for the withdrawal of foreign military personnel 'present otherwise than under the authority of international agreements'. Each side reads that clause differently, since the Treaties of Alliance and Guarantee are themselves international agreements.

1983: the TRNC proclamation

On 15 November 1983 Rauf Raif Denktaş proclaimed the Turkish Republic of Northern Cyprus. Three days later UNSC Resolution 541 called the declaration legally invalid and asked states not to recognize it; Resolution 550 (1984) repeated this. The TRNC says it exercises the Turkish Cypriot people's right to self-determination and political equality. Only Türkiye recognizes it.

Key milestones in the negotiating corridor

Date	Event	What it recorded
1959-02-11 / 1959-02-19	Zurich and London Agreements	Foundation of the 1960 partnership republic
1960-08-16	Republic of Cyprus and Treaty of Guarantee	Three guarantor powers; Article IV right to act
1963-11-30 to 1964-03-04	13 proposals, 21 December fighting, UNSC 186	End of shared government; UN force deployed
1974-07-15 / 1974-07-20	Coup and Peace Operation	De facto division along a ceasefire line
1977 and 1979	High-Level Agreements	Both sides accepted a bicommunal, bizonal federation as the agenda
1983-11-15	TRNC proclaimed	UNSC 541 (1983) and 550 (1984) deny recognition
2004-04-24	Annan Plan referendums	64.91% Turkish Cypriot Yes; 75.83% Greek Cypriot No
2004-05-01	EU accession of the Republic of Cyprus	EU law suspended in the north under Protocol 10
2017-06-28 to 2017-07-07	Crans-Montana Conference	Talks ended without agreement on security and guarantees
2021-04-27 to 2021-04-29	Geneva informal 5+UN meeting	UN reported no common ground for formal negotiations
2024-10-15	New York UN informal meeting	Sides remained apart on the model of settlement

Settlement efforts, 2004–2024

The Annan Plan produced the sharpest asymmetry in the record. Turkish Cypriots, led politically by Mehmet Ali Talat's camp, approved it with 64.91%. Greek Cypriots rejected it with 75.83% after President Tassos Papadopoulos urged a No. The Republic of Cyprus then joined the EU on 1 May 2004 as a whole island in law, with the acquis suspended in the north. Turkish Cypriot and Turkish sources describe this as a reward for rejection. Greek Cypriot sources reply that the plan's security, property and implementation provisions were unacceptable, and that EU membership was agreed in 1999–2003 independently of the vote. The full account is in The Annan Plan Referendum of 24 April 2004.

At Crans-Montana (June–July 2017), UN Secretary-General António Guterres presented a framework covering security and guarantees, territory, property, equivalence and effective participation. The talks ended without agreement. Greek Cypriot and UN-adjacent accounts stress disagreement over the future of guarantees and Turkish troops. Ankara and Turkish Cypriot officials say that the Greek Cypriot side would not accept political equality and rotating presidency in a form that guaranteed Turkish Cypriots effective participation. The Geneva 5+UN meeting (April 2021), with the two sides plus the three guarantors and the UN, ended with Guterres stating that there was no common ground to begin formal negotiations. At the 15 October 2024 UN meeting in New York, the sides again remained apart on the nature of a solution.

Key Players & Positions

United Nations

The UN's long-standing parameters are in Security Council resolutions. Resolution 1251 (1999) reaffirmed a Cyprus settlement based on a single sovereignty and international personality, a single citizenship, and political equality in a bicommunal, bizonal federation. Resolutions 541 and 550 reject the TRNC as a legal entity. The Secretary-General's reports and mandate renewals for UNFICYP carry this framework forward. Guterres's own statements after Geneva 2021 stressed that, in his reading, there was no common ground for formal negotiations on a solution at that time.

Republic of Cyprus (Greek Cypriot administration)

The Republic of Cyprus, led by President Nikos Christodoulides, seeks resumed UN-led talks toward a bizonal, bicommunal federation with political equality, as set out in the resolutions above. Its official documents describe the Treaty of Guarantee's intervention clause as obsolete in an EU member state and reject Article IV as permission for military action. It treats the 1974 operation as an invasion and the TRNC as a secessionist entity. It points to the missing persons, displaced Greek Cypriots and property in the north. Ankara calls this administration the Greek Cypriot Administration of Southern Cyprus (GCASC), since it argues that it has not represented Turkish Cypriots since 1963. This guide uses 'Republic of Cyprus' for the internationally recognized government and 'GCASC' when citing Ankara's usage.

Greece and the United Kingdom

Greece, a guarantor, supports a settlement based on UN resolutions and EU principles, and its officials have called for ending the guarantee-and-intervention system and withdrawing Turkish troops. The UK, also a guarantor and holder of the Sovereign Base Areas, supports a UN-led settlement and has repeatedly said it would respect any outcome agreed by both communities. It has said that it would not support a two-state outcome that rejects the UN framework.

European Union

The EU's primary-law position is Protocol 10 to the 2003 Act of Accession, which suspends the acquis in the areas where the Republic's government does not exercise effective control. The Council and European Council conclusions state support for a comprehensive settlement in the UN framework, in line with relevant Security Council resolutions and the principles on which the EU is founded. EU institutions have said they do not accept two-state outcomes, and they have supported measures against Turkish drilling in disputed waters. See Fact Check: Does the 'Seville Map' Set Maritime Boundaries in the Eastern Mediterranean? for how this overlaps with maritime delimitation.

TRNC and Turkish Cypriots

The TRNC government and the Turkish Cypriot leadership around Ersin Tatar adopted a sovereign-equality, two-state line from 2020–2021. Turkish Cypriot politics is not uniform. Parties and leaders in the CTP tradition, such as Talat, historically campaigned for the federal Annan Plan, and positions have shifted over time with elections. Readers should check current statements by the Turkish Cypriot leadership. The TRNC has observer status in the Organization of Turkic States (since the Samarkand summit of 2022) and takes part in the Organisation of Islamic Cooperation under the name 'Turkish Cypriot State'.

🇹🇷 Official Policy · Treaties & Primary Sources

Türkiye's Position

Ankara's official line, as set out in statements by the Republic of Türkiye Ministry of Foreign Affairs (MFA) and the Presidency, rests on five points:

Guarantor rights remain in force. According to the Turkish Foreign Ministry, the 1960 Treaty of Guarantee (Articles I, II and IV) is a binding treaty. Ankara argues that the 15 July 1974 coup, aimed at ENOSIS, breached Articles I and II. It also holds that, after consultation with the UK and with no common action possible, Article IV entitled it to act on 20 July 1974. The Turkish MFA describes the operation as a lawful exercise of that right.
Federation is exhausted. Ankara argues that more than 50 years of talks (the 1977 and 1979 High-Level Agreements, the Annan Plan referendums of 24 April 2004, Crans-Montana in 2017, Geneva in April 2021, and New York on 15 October 2024) have not produced a federation because the Greek Cypriot side will not share power and prosperity on the basis of equality. Turkish officials cite the 2004 vote asymmetry (64.91% Yes against 75.83% No) as the clearest evidence.
Talks must start from sovereign equality and equal international status. President Recep Tayyip Erdoğan, in addresses to the UN General Assembly since 2021, has called on states to recognize the realities on the island. According to Ankara, the 1960 republic was a partnership of two co-founding peoples. UNSC Resolution 186 (1964) set up a status asymmetry that Turkish Cypriots did not accept. The way forward, in Ankara's view, is to affirm the Turkish Cypriots' inherent sovereign equality and equal international status, followed by cooperation between two states.
Turkish Cypriots hold equal rights over the island's offshore resources. The Turkish MFA says hydrocarbons around Cyprus belong to both peoples and must be managed through joint decision-making and revenue sharing. The TRNC tabled proposals in 2011, 2012 and 2019, and Erdoğan proposed an Eastern Mediterranean conference including all coastal states and the Turkish Cypriots in 2020. Ankara pairs this with its maritime-delimitation position: the 2011 Türkiye–TRNC continental-shelf agreement (21 September 2011) and its 2020 UN registration. See Eastern Mediterranean Corridors and From Fatih to Oruç Reis.
End the isolation of Turkish Cypriots. Ankara links its position to ending the isolation of the Turkish Cypriots and to wider acceptance of the TRNC, citing its observer status in the Organization of Turkic States.

Legal and historical basis, and the counter-argument. Ankara grounds its case in the Zurich–London texts, the 1960 constitution's two-community structure, Article IV of the Treaty of Guarantee, and the 1964 and 1974 record. The strongest objections come from other parties. The Republic of Cyprus and Greece argue that Article IV permits action only to restore the constitutional order, not partition or lasting presence, and that UN Charter Article 2(4) and Resolutions 353, 541 and 550 apply. Turkish officials respond that the same resolutions did not name Türkiye as an aggressor, that Resolution 353 itself refers to forces present 'under the authority of international agreements', and that the rights and obligations of the 1960 treaties cannot be waived by one party's later membership of the EU. The partition prohibition in Article I also becomes an argument against two states. Ankara answers that two states created by the consent of both peoples, after the partnership was ended, are not unilateral partition. That is a political-legal dispute, not a settled legal point. See also Borders & Blocs on Article IV and WorldPoliticsDaily's fact check.

Source Comparison

The table sets out how the main framings differ and which documents let readers check them.

Issue	Common international / Greek Cypriot framing	Turkish and TRNC framing	Primary documents to check
1963–64	Turkish Cypriots withdrew from state organs; Makarios's proposals were a constitutional reform	Greek Cypriot forces ended the partnership by force on 21 December 1963	1960 constitution; UNSC 186 (1964); UN Secretary-General's 1964–65 reports
1974	Invasion and occupation after the coup	Lawful use of Article IV after the 15 July coup	Treaty of Guarantee; UNSC 353 (1974); MFA statements
Article IV	Allows restoration of the constitutional order only, not partition or lasting presence	Allows action 'to re-establish the state of affairs'; partnership republic could not be restored while one side blocked it	Treaty of Guarantee, Articles I, II, IV
Annan Plan	Greek Cypriots rejected a flawed plan; accession was independent of the vote	A Turkish Cypriot Yes was followed by Greek Cypriot rejection, then EU entry for one side	Referendum results of 24 April 2004; Protocol 10
Crans-Montana	Failure over security and guarantees	Failure over political equality and the Greek Cypriot refusal to share power	UN Secretary-General's report, July 2017
TRNC status	Legally invalid entity; only Türkiye recognizes it	A state exercising self-determination; talks should recognize two equal states	UNSC 541 (1983) and 550 (1984); TRNC and MFA statements
Settlement model	A federation under UNSC 1251 (1999) is the only agreed basis	Federation exhausted after decades; sovereign equality should be the starting point	UNSC resolutions; Guterres's Geneva 2021 and New York 2024 remarks

How to read the sources

Check each claim against the instrument it cites. Articles I, II and IV of the Treaty of Guarantee and the text of UNSC 186, 353 and 541 are short and publicly available.
Separate fact from reading. That the coup took place on 15 July 1974 and the referendum figures were 64.91% and 75.83% are facts. Whether Article IV permits what followed is a legal dispute.
Look for the other side's own documents. The Republic of Cyprus, Greece, the EU and the UN publish their positions, and a fair account quotes them rather than a rival's summary.

What to watch

UN process. Whether the Secretary-General's personal envoy can convene a format that the Greek Cypriot and Turkish Cypriot sides, Türkiye, Greece and the UK all accept.
Turkish Cypriot leadership. Elections and leadership changes in the TRNC may shift the balance between two-state and federal lines.
Maritime questions. Energy and cable projects in the Eastern Mediterranean, and the 2025 IOC-UNESCO registration of Türkiye's marine spatial plan.
EU–Türkiye relations. How far the EU links Cyprus to wider relations with Ankara.

Treaty of Guarantee (1960): the treaty between Cyprus, Greece, Türkiye and the UK whose Article IV gives each guarantor the right to act, after consultation, to restore the constitutional order.
Bizonal, bicommunal federation: the settlement model in UN resolutions, with two constituent states and political equality. Turkish officials say it is exhausted.
Sovereign equality / two-state vision: Ankara and TRNC formulation that the two peoples have equal sovereign status and should coexist as two states.
ENOSIS: the Greek Cypriot nationalist goal of union with Greece, which the Treaty of Guarantee prohibits.
Green Line: the UN-patrolled buffer zone dividing the island, first drawn in Nicosia on 30 December 1963.
Protocol 10: the part of the 2003 Act of Accession that suspends EU law where the Republic's government lacks effective control.
GCASC: Ankara's term for the Greek Cypriot administration of the Republic of Cyprus.

Related guides on this site:

Sister-publication analyses:

Corridors of Diplomacy presents global affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. We state this editorial stance openly and attribute claims to primary sources such as treaty texts, UN documents, official statements and archival records, so that readers can verify them independently. — Corridors of Diplomacy Editorial Team

Frequently asked questions

What are Türkiye's guarantor rights in Cyprus?

Under the 1960 Treaty of Guarantee, Türkiye, Greece and the United Kingdom guarantee Cyprus's independence, territorial integrity and constitutional order. Article IV requires consultation after a breach and, where common action is not possible, reserves each guarantor's right to act solely to restore the situation created by the treaty. Ankara cites this article for its 20 July 1974 Peace Operation, while Greek Cypriot and many international sources dispute how far it allows the use of force.

What is the Turkish and TRNC two-state position?

Ankara and the TRNC argue that decades of talks on a federation, from the 1977 and 1979 High-Level Agreements to New York in October 2024, have failed to produce a settlement. They say talks must begin by affirming the sovereign equality and equal international status of Turkish Cypriots, with two states then cooperating on the island. The UN, EU, Greece and the Republic of Cyprus still base their positions on a bizonal, bicommunal federation.

Why did the Annan Plan referendums of 2004 matter?

On 24 April 2004, 64.91% of Turkish Cypriots voted Yes and 75.83% of Greek Cypriots voted No. The Republic of Cyprus joined the EU on 1 May 2004, with EU law suspended in the north. Turkish sources see this as a lasting asymmetry, while Greek Cypriot officials say the plan's security and property provisions were unacceptable and that accession was decided independently.

Is the TRNC recognized by any country other than Türkiye?

No. Only Türkiye recognizes the TRNC as a state, and UN Security Council Resolutions 541 (1983) and 550 (1984) call its proclamation legally invalid. The TRNC has observer status in the Organization of Turkic States and participates in the Organisation of Islamic Cooperation as the 'Turkish Cypriot State'.

What happened at Crans-Montana, Geneva and New York?

At Crans-Montana (June–July 2017) the UN-led talks ended without agreement on security, guarantees and political equality. At the Geneva 5+UN meeting in April 2021, Secretary-General Guterres reported no common ground for formal negotiations. At the New York meeting on 15 October 2024, the sides remained apart on the model of settlement.

Does the Treaty of Guarantee's ban on partition rule out a two-state solution?

Greek Cypriot and Greek sources argue that Articles I and II prohibit partition and therefore a two-state outcome. Ankara replies that two states created with the consent of both peoples, after the 1960 partnership was ended in 1963, are not a unilateral partition. This is a contested legal and political question, and no international court has ruled on it.

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