Turkish President Recep Tayyip Erdogan makes a speech as party leader at the Justice and Development (AK) Party group meeting in the Grand National Assembly of Turkey. Erdogan said Libyan general Khalifa Haftar deserved "a lesson" as a breakdown of talks in Moscow threw in doubt a planned international peace conference in Berlin this Sunday. Photo: AFP

 Turkey blocked a request from Cyprus on Tuesday to participate as an observer at the Conference on Disarmament in Geneva, amid growing tensions between the two countries.

Cyprus was one of a long line of countries to request the right to serve as observers in the first session of the year of the 65-member Geneva-based body.

All but one request were accepted by the necessary consensus.

But when the request from Cyprus was raised, Turkey's representative requested the floor.

Ankara, he said, has in the past refrained from blocking Cyprus' participation, and had simply voiced its displeasure in a letter at the end of each session.

But that has changed, he said, stressing that "Turkey will not support this particular request this year."

The US and the EU lamented the Turkish move.

"It is unfortunate that Turkey has decided to block Cyprus from participating in the work of the conference," said the US Ambassador to the conference, Robert Wood, urging "Turkey to reconsider its objection."

Turkey's objection came amid growing tensions over Ankara expanding its claims over a large gas-rich area which Cyprus says includes its territorial ­waters.

Cyprus has aligned itself with Greece, Israel and Italy in planning an ambitious 2,000-kilometer eastern Mediterranean gas pipeline to Europe despite Turkey's hostility to the deal.

Cyprus is divided between the Greek Cypriot-run south - an EU member state - and the Turkish Cypriot north, where Ankara has stationed tens of thousands of troops since 1974 following an Athens-­engineered coup.

Turkey insists the Turkish Republic of Northern Cyprus - recognized only by Ankara - has the right to explore in the island's waters.

Cyprus has also joined forces with Greece, Israel, Egypt and France in condemning a maritime and security accord that Turkey signed with Libya's UN-recognized government.