BERLIN — Germany's foreign minister headed Tuesday to Greece and Cyprus, pledging "full solidarity" with them in their dispute with Turkey over sea boundaries and drilling rights in the eastern Mediterranean.
The United States also issued a strong rebuke to Ankara Tuesday over the "calculated provocation" of its energy prospecting activities.
Germany holds the rotating European Union presidency and before departing Berlin, Foreign Minister Heiko Maas said Greece and Cyprus had both German and EU backing but urged an "honest effort on all sides" to find a solution.
Greece on Monday accused neighbor Turkey of undermining efforts to ease a crisis over eastern Mediterranean drilling rights, after Ankara redeployed a survey vessel for new energy exploration in disputed waters — including an area very close to a secluded Greek island.
The move reignited tensions over sea boundaries between Greek islands, Cyprus and Turkey's southern coast, which had flared up over the summer, prompting a military build-up, bellicose rhetoric and fears of a confrontation between the two NATO members and historic regional rivals.
The U.S. State Department issued a statement deploring Turkey's move, saying it "unilaterally raises tensions in the region and deliberately complicates the resumption of crucial exploratory talks between our NATO Allies Greece and Turkey."
"We urge Turkey to end this calculated provocation and immediately begin exploratory talks with Greece," the statement added." Unilateral actions cannot build trust and will not produce enduring solutions."
The Turkish search vessel, Oruc Reis, left the port of Antalya on Monday for a mission expected o end Oct. 22. According to Greek media it is escorted by warships.
Maas stressed that talks between the nations can only work in a "constructive atmosphere" and appealed "to Turkey not to close the window for dialogue that has just opened with Greece through unilateral measures."
"Ankara must stop alternating between relaxation and provocation if the government is interested in talks, as it has repeatedly said," he said.
Renewed Turkish gas exploration in the disputed areas would be "a major setback to efforts to de-escalate and thus also for the further development of EU-Turkey relations," Maas said.