Ankara had withdrawn the research vessel last month, allowing for talks with Athens.
ATHENS — The Turkish research ship at the center of an escalation of tensions in the Eastern Mediterranean returned to waters claimed by Greece on Monday.
The Oruç Reis, a seismic vessel owned by Turkey’s General Directorate of Mineral Research and Exploration, will resume its energy exploration efforts until October 22, according to a navigational warning issued by Ankara.
The ship will pass close to Greece’s easternmost islands, a move likely to mar planned diplomatic talks between Athens and Ankara.
Turkey had recalled the ship last month, allowing long-stalled negotiations with Athens to restart following weeks of surging tensions over Ankara’s search for hydrocarbons in waters claimed by Greece and Cyprus.
No date for the resumption of talks had been set, however, and Turkey at the time said the Oruç Reis would resume its exploratory activity.
In recent days, both sides announced naval drills, ratcheting up tensions once more. Athens said it would conduct a military exercise on October 29 — Turkey’s national day — while Ankara issued a warning for a military exercise on October 28, Greece’s national day.
Greece’s foreign ministry said the ship’s return “constitutes a major escalation and direct threat to peace and security in the region” and urged Ankara to revoke its decision. It added that the move made evident “Turkey’s unreliability and the fact that it does not sincerely desire dialogue.”
On Sunday, the Turkish foreign ministry issued a statement criticizing Greece’s foreign minister, who in an interview had blamed Turkey for the suspension of diplomatic talks in 2016.
“Exploratory talks were suspended in 2016 upon the request of Greece,” foreign ministry spokesman Hami Aksoy said, adding: “The fact that Greece has been attempting to use the EU as a trump card against Turkey, instead of resolving her issues in the Aegean and the Eastern Mediterranean through a sincere dialogue with our country, is a futile endeavor.”
Another Turkish survey ship, the Barbaros Hayreddin Paşa, is conducting seismic work off Cyprus until November 9.
Greece and Cyprus want to raise the issue at this week’s summit of EU leaders. Earlier this month, EU leaders warned Ankara could face sanctions over its activities in the Eastern Mediterranean.