What Is the 1960 Treaty of Guarantee and Why Does It Matter for Cyprus?

Why It Matters

The 1960 Treaty of Guarantee is the legal instrument that gave Greece, Türkiye and the United Kingdom a formal role as guarantors of Cyprus's constitutional order. It matters because Türkiye has relied on it since 1974 to justify its military presence on the island, while the Republic of Cyprus and others argue that it never authorised the use of force. Almost every attempt to settle the Cyprus question has had to deal with whether the guarantee system should be kept, reformed or abolished. For the wider story, see The Cyprus Dispute Explained: 1960, 1963, 1974 and Today.

Background: How the Treaty Came About

The treaty was one of several instruments negotiated in Zurich and London in February 1959 and signed in Nicosia on 16 August 1960, the day Cyprus became independent from British rule. The package set up a bi-communal state in which Greek Cypriots and Turkish Cypriots shared power under a constitution with power-sharing safeguards.

The settlement rested on several documents:

• Treaty of Establishment: kept two British Sovereign Base Areas, Akrotiri and Dhekelia, under UK sovereignty.
• Treaty of Alliance: between Cyprus, Greece and Türkiye, allowing small Greek and Turkish military contingents on the island.
• Treaty of Guarantee: the political-legal safeguard for the whole arrangement.
• The 1960 Constitution: the 'Basic Articles' of which the guarantee protects.

The background to the arrangement was a competition between two aims. Many Greek Cypriots had sought enosis (union with Greece), while many Turkish Cypriots, supported by Ankara, favoured taksim (partition). The treaty tried to close off both options at once.

What the Treaty Says

The treaty is short. Its core provisions are summarised below; the wording of Article IV is quoted from the treaty as commonly cited.

Two features explain most of the later argument. First, the treaty gives rights to three outside states, not only to Cyprus. Second, Article IV does not define what 'action' means, and it does not mention military force explicitly.

The sequence the treaty envisages

1. A breach occurs (for example, a move toward union or partition, or a breakdown of the constitutional order).
2. The guarantors consult (Article III).
3. If joint action is impossible, each guarantor may act individually, with the sole aim of restoring the treaty's state of affairs (Article IV).

Key Players and Positions

Republic of Cyprus and the Greek Cypriot side

Nicosia argues that the Republic is a sovereign UN member and that no treaty can give other states a right to use force against it. It points to the UN Charter: Article 2(4) prohibits the threat or use of force against the territorial integrity of states, Article 103 gives Charter obligations priority over conflicting treaty obligations, and Article 53 bars enforcement action by regional arrangements without Security Council authorisation. It also argues that Article IV, even if valid, was limited to restoring the 1960 order and did not permit a lasting military presence or the division of the island. In peace talks, the Greek Cypriot side has generally sought the end of unilateral guarantor intervention rights.

Greece

Greece was a guarantor, and Athens has in the past accepted that the Greek junta's role in the 15 July 1974 coup was a serious breach. In modern settlement talks, Greek governments have supported replacing the 1960 guarantee system with a new security arrangement, often involving the UN or the EU.

United Kingdom

The UK is both a guarantor and a sovereign-base holder. In 1974 it did not join Türkiye in joint action and did not itself intervene militarily. Britain participated in the Geneva conferences of July and August 1974 and has since said it would support whatever arrangement the Cypriot communities agree on.

The United Nations

Security Council Resolution 353 (20 July 1974) called for a ceasefire, for the withdrawal of foreign military personnel present other than under international agreements, and for Greece, Türkiye and the UK to enter negotiations. Later resolutions, including 541 (1983) on the 'Turkish Republic of Northern Cyprus' declaration, called that declaration legally invalid. The UN has since supported a settlement based on a bi-communal, bi-zonal federation with political equality, though positions have evolved.

The Counterarguments in Detail

The disagreement is not mainly about what the treaty says, but about how it interacts with later law and with what happened after July 1974.

• Force versus 'action': Critics read Article IV narrowly, as permitting diplomatic, economic or limited measures, and note that it does not explicitly mention force. Supporters of Ankara's reading say 'action' must include military measures, since the guarantors held no other practical means.
• UN Charter hierarchy: Under Article 103, Charter obligations prevail over conflicting treaty obligations. Cyprus and many scholars argue that a right of unilateral military intervention conflicts with Article 2(4).
• Proportionality and purpose: Even those who accept that the coup was a breach often argue that the 'sole aim' of Article IV was restoration of the 1960 order. They say the continued presence of troops since 1974 and the 1983 declaration of a separate state went beyond that aim.
• Legal status of the treaty itself: Some Greek Cypriot commentators argue the treaty conflicts with sovereign equality and may be invalid. Ankara and many international lawyers reject this, noting that the treaty was accepted by independent Cyprus and is tied to the constitution's Basic Articles.

Source Comparison

Sources frame the same events in different terms:

Readers can compare the sources directly; our approach is set out in Editorial Principles: How WorldPoliticsDaily Separates Fact from Position. For claims about Türkiye that circulate in the international press, see Fact Check: Claims About Türkiye in International Media.

Why It Still Matters Today

The guarantee question was one of the main sticking points at the 2017 Crans-Montana conference, convened under UN auspices, which ended without agreement. Security and guarantees also connect to wider regional questions such as energy and maritime rights, covered in Eastern Mediterranean Maritime Disputes Explained: Rights, Maps and Positions. Any lasting settlement will have to answer who protects whom, and under what authority.

Related Reading

• The Cyprus Dispute Explained: 1960, 1963, 1974 and Today
• Eastern Mediterranean Maritime Disputes Explained: Rights, Maps and Positions
• About WorldPoliticsDaily: Who We Are and Why We Publish

Perspective Note

WorldPoliticsDaily presents global affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources.

By WPD Editorial Team.

Cross-Publication Dossiers & Sister Desk Perspectives

For complementary primary-source analysis across our specialist editorial network, consult:

• Doctrine Review: Cyprus and the 1960 Treaty of Guarantee: What It Says and Why It Matters — The 1960 Treaty of Guarantee in Cyprus explained: what Article IV says, how 1963-74 unfolded, where the UN talks stand, and Türkiye's official position.
• Interstate Journal: Cyprus and the 1960 Treaty of Guarantee: What It Says and Why It Matters — 1960 Treaty of Guarantee Cyprus explained: what Article IV allows, whether it is still valid and why the island is divided, from 1960 to the two-state debate.
• Political Ledger: The Cyprus Issue: 1960 Treaty of Guarantee, Turkish Cypriot Equality and the Two-State Doctrine — Cyprus issue 1960 Treaty of Guarantee two-state solution explained: from EOKA and 1963 to 1974, the TRNC, failed federation talks, and each side's case.