Turkey on Friday accused France of acting like a bully and hit out at Greece as EU foreign ministers confronted an emerging crisis in the energy-rich eastern Mediterranean.
The search for oil and gas in disputed waters not far from Cyprus has pitted Turkey against its uneasy NATO ally Greece and the entire EU bloc.
Turkey's decision to send a scientific vessel accompanied by a small navy fleet into the volatile region on Monday prompted Greece to dispatch in its own military assets to observe what was going on.
France on Thursday also announced it was "temporarily reinforcing" its presence in the eastern Mediterranean in support of Greece.
That only further hurt France's relations with Turkey -- already damaged by opposing approaches to the Libya conflict and other parts of the Middle East -- and saw the diplomatic rhetoric rise another notch.
"France especially should avoid steps that will increase tensions," Turkish Foreign Minister Mevlut Cavusoglu said on a visit to Switzerland.
"They will not get anywhere by acting like bullies, whether in Libya, the northeast of Syria, in Iraq or the Mediterranean."
French President Emmanuel Macron retorted that his view on Libya and the Mediterranean were "convergent" to those of US President Donald Trump and UAE strongman Sheikh Mohamed bin Zayed Al-Nahyan.
"Our interests in peace and security are common there," Macron said in Paris. "We will ensure that it is respected."
- Erdogan hints at incident -
Turkish President Recep Tayyip Erdogan underscored the fraught nature of the standoff by warning on Thursday of a "heavy price" to pay for those who threaten Turkey's Oruc Reis research ship.
"We can't let even the smallest attack go without an answer," Erdogan reaffirmed on Friday.
The president said "something like this" happened to the Oruc Reis on Thursday but provided no details.
Another warship accompanying Oruc Reis "gave the necessary response, and then they withdrew to their ports," Erdogan said, without specifying which nation's ships allegedly confronted Turkey's.
The Greek defence ministry denied being involved in any incident with the Oruc Reis.
Cavusoglu said that Turkey was seeking a peaceful end to the crisis and was only expecting "common sense" from Greece.
"Of course we do not wish to escalate," said Cavusoglu.
Turkey argues that Greece is using its control of a few tiny islands off the coast of Turkey to claim an outsized share of the Mediterranean Sea.
It also cites examples of past international agreements that gave the coastal power the right to waters despite another nation's islands near its shores.
- Wary of Erdogan -
German Chancellor Angela Merkel has acted as the primary arbiter in the increasingly unpredictable dispute.
Erdogan had followed Merkel's urgings and suspended the Oruc Reis mission last month to give talks another chance.
Greece then signed a maritime agreement with Egypt that appeared aimed at countering a similarly controversial one Turkey had signed with the UN-recognised government in Libya last year.
The Egyptian deal was followed by Erdogan's decision to push ahead with the Oruc Reis mission this week.
"These tensions are worrying," Merkel's spokesman Steffen Seibert said on Friday.
Erdogan said he agreed with Merkel by phone on Thursday to enter talks aimed at "softening" the standoff once the Oruc Reis pulls out of the region on August 23.
A European official told AFP that Merkel had warned Erdogan last month that Turkey would face EU sanctions if it drills in Cypriot waters or off the Greek island of Kastellorizo.
The diplomatic jostling also saw Greek Foreign Minister Nikos Dendias seek Washington's backing at a meeting in Vienna with US Secretary Mike Pompeo.
Yet both Washington and Brussels are keen to avoid head-on confrontations with Erdogan.
The EU foreign ministers agreed by videoconference on Friday to take up the standoff at their next face-to-face talks.
And the US State Department followed Pompeo's meeting with Dendias by simply stressing "the urgent need to reduce tensions in the eastern Mediterranean".