Tensions between Greece and Turkey in the eastern Mediterranean reignited Monday after Ankara sent a research ship into a hotly disputed area.

The Oruc Reis of Turkey intends to carry out work south of the Greek island of Kastellorizo, which is close to Turkey's coast. The move prompted Greece to issue a furious new demand for EU sanctions on Ankara in a row over offshore exploration rights.

Greece's foreign ministry described the new voyage as a "major escalation" and a "direct threat to peace in the region." 

Relations between Greece and Turkey, two NATO members, are complicated by a range of disputes, from jurisdiction in the Mediterranean to ethnically split Cyprus.

Read more：Northern Cyprus to open coast of disputed town of Varosha

Ankara had withdrawn the vessel from contested waters in the eastern Mediterranean last month to "allow for diplomacy" before an EU summit at which Cyprus sought sanctions against Turkey.

At the summit, the EU said it would punish Turkey if it continued operations in the region and that sanctions could be imposed as soon as December.

Greek government spokesman Petsas said Turkey had done the opposite of what it should have, and the EU did not need to wait two months before taking action.

"So the only issue here is to activate more drastic solutions, for Turkey to feel more stick and less carrot this time," Petsas said.

France has expressed its concern after the Turkish vessel, the Oruc Reis, began its voyage. French Foreign Ministry spokeswoman Agnes von der Muhll said Paris expects Turkey to meet its commitments, abstain from new provocations and show concrete evidence of good faith.

Turkish Defence Minister Hulusi Akar said Ankara's operations were within its continental shelf and it expected Greece to refrain from steps escalating tensions.

"They (Greece) are doing everything to escalate tensions," Akar said. "The Navy will provide the necessary escort and protection to our vessels as needed."

Turkish Energy Minister Fatih Donmez wrote on Twitter that Turkey would "continue to explore, dig and protect our rights."

(With input from agencies)