Despite widespread denunciation and worries it could undercut planned talks and kick off a conflict, the The Turkish energy research vessel Oruc Reis violated Greek waters off the island of Kastellorizo to hunt for oil and gas.

Greece's state-run Athens-Macedonia News Agency (ANA-MPA) said the vessel was nearing the island the morning of Oct. 13, setting off a scramble by Greek and European Union officials about how to stop it.

The move by Turkish President Recep Tayyip Erdogan, showing his further disdain for Greece and the EU – which pulled talks of sanctions off the table to give diplomacy a chance – threatened to pull the plug on talks in Ankara.

Turkey disputes Greece's Continental Shelf and, under a maritime deal with Libya no other country recognizes – claimed waters off Greek islands, including Crete, and Erdogan said drilling will proceed under any circumstances.

Both Greek Prime Minister Kyriakos Mitsotakis and Cypriot President Nicos Anastasiades withdrew their insistence on EU sanctions on Turkey for now but are complaining Turkey has done an end-around.

Violating rules of the sea, the Oruc Reis reportedly turned off its global positioning system in an apparent attempt not to be tracked and as Greek and EU officials were firing off a fusillade of protests.

Erdogan, who had pulled the ship away from Kastellorizo, along with warships he sent as escorts, has shown a scunner to Greece and the EU even as he said the resolution should be diplomatic and political while threatening a conflict.

The EU had given Turkey until the end of the year to reach a resolution with Greece – Erdogan won't talk to Cyprus, which he doesn't recognize – or possibly face sanctions, althoug the bloc has been reluctant to tangle with him, fearful he will unleash more refugees and migrants through Greece and its islands.

Greece was prepared for “any eventuality” in the tensions with Turkey, State Minister Giorgos Gerapetritis told state-run broadcaster ERT, but he didn't say if that meant going to battle stations.

“When your alleged interlocutor is the President of Turkey, nothing is entirely predictable,” he said, adding that's why Greece insisted on a clause in the EU decision in a showdown with Turkey that any talks come only during peace.

Erdogan's gambit, apparently testing the resolve of Greece and the EU, led German Foreign Minister Heiko Maas to cancel a visit to Ankara but his office refused to say it was over the Oruc Reis.

Germany, home to 2.774 million people of Turkish heritage, is trying to broker the talks after Chancellor Angela Merkel said she would scuttle any attempts at sanctions on Turkey, praising Erdogan for holding back waves of refugees and migrants.

Before he changed his plans – he still has scheduled stops in Athens and Nicosia on Cyprus – Maas said Turkey should ratchet down.  "Ankara must end the interplay between detente and provocation if the government is interested in talks – as it has repeatedly affirmed," he said.

Erdogan, who complained the EU is siding with EU members Greece and Cyprus and being unfair to Turkey, told European Council President Charles Michel – representing all 27 countries – he wants “concrete steps” to improve relations, said Reuters.

He said he wants a regional conference with Eastern Mediterranean states, and that Greece was "continuing steps to escalate tensions in the eastern Mediterranean despite Turkey's well-intentioned approach,” blaming only Greece for the trouble.