Turkey has stoked tensions with Cyprus and Greece by embarking on a new round of exploration activity in the East Mediterranean, dampening hopes for a quick resolution of conflicting claims to potential hydrocarbon resources in the region.

Turkey has vowed to soon resume similar work in disputed waters with Greece, dispelling speculation of a pause in exploration activities with the recent return home of its seismic vessel Oruc Reis.

The mission of the drillship Yavuz off Cyprus is being extended until 12 October, accompanied by naval frigates in a show of force by the Turkish government.

A maritime naval notice — known as a Navex — warned on 15 September that “all vessels are strongly advised not to enter” the area.

Ankara and the internationally recognised Greek administration of Cyprus in Nicosia have long been at odds over territorial waters of the Mediterranean island nation, which was split after a 1974 Turkish invasion spurred by a brief coup engineered by the military junta then ruling Greece.

Turkey argues the self-styled Turkish Republic of North Cyprus, recognised only by Ankara, has its own legitimate maritime and exploration rights.

As such, Turkey questions Cyprus’ right to explore off the island, arguing the Greek administration does not represent all the Cypriots.

Cyprus is a member of the European Union and is strongly supported by Greece in its upstream activities off the divided island, where supermajors Shell, ExxonMobil and Total have made significant gas discoveries in the past decade.

Regional rivalry is, however, proving an impediment to both exploration and development work.

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Greece said in recent days it is ready to give diplomacy a chance following the withdrawal of the Oruc Reis from a disputed region.

Turkish Foreign Minister Mevlut Cavusoglu said the vessel returned home on 12 September to replenish supplies and maintenance and its return did not mean a “concession” in Turkey’s exploration policy in the region.

“Greece can perceive it as a step back in the face of our determination,” he said. “It is suffering the insecurities of a small country.”

The Turkish Energy Ministry said in a separate statement that after undergoing “examination and care, the vessel would continue its seismic search and research activities".

Greek Prime Minister Kyriakos Mitsotakis had welcomed the return of the vessel from an area south of the Greek island of Kastellorizo, seeing it as an opportunity to engage in diplomacy.

Similarly, Cavusoglu said Ankara was open to negotiations with Greece without pre-conditions to try to resolve the dispute concerning the East Mediterranean.

“The two neighbouring countries can meet directly. The statements made by the Greek prime minister are positive and moderate. But if he insists on the pre-conditions to sit at the table with us, we will put forward our prerequisites,” he said.

Tensions have been on the rise in the past month between the two uneasy neighbours amid stepped-up exploration and naval exercises by both sides, which had increased fears of an accidental confrontation. The EU is considering punitive measures against Turkey in a show of solidarity with members Cyprus and Greece.

Turkey has made it clear it would not be cowed into concessions by the EU.

Anthony Skinner, an analyst at risk analysis company Verisk Maplecroft, said: "The EU’s ability to force Turkey to cease all exploration activities in the East Mediterranean will, in our view, remain inhibited by its lack of consensus on how to manage Ankara.

"Europe is unlikely to wave a big enough stick to force capitulation. The only way biting sanctions would be imposed would be through a unanimous vote from all 27 EU members."

Skinner labelled the prospect of this happening as "unlikely", however. "While France, Greece and Greek Cyprus advocate a hardball approach to Turkey, EU Council President Germany wants to avoid escalation, opting instead for ongoing talks where an expanded customs union agreement sits on the table with limited sanctions in the back pocket. "Italy, Spain and Malta likewise prefer to exhaust the diplomatic track before applying coercive measures should Turkey continue to explore unilaterally in the East Mediterranean’s disputed waters," he added.