Turkish President Recep Tayyip Erdogan waved off a new oil and gas drilling ship on Tuesday as it heads for the sensitive waters of the Eastern Mediterranean.
Mr Erdogan said the Abdulhamid Han would explore in Turkish sovereign waters and said that "we don't have to ask for permission from anyone".
On a visit to the port, where he boarded the drilling ship, he said the first extracted gas could be put to use in Turkey as soon as next year once 10 required wells are ready.
"Our Abdulhamid Han drill ship is the symbol of Türkiye's new vision for the field of energy," he said.
Turkey's previous drilling ventures in the Mediterranean, some of them escorted by warships, have ratcheted up tension with Greece and Cyprus after they strayed into contested waters.
Turkey disputes Greece's claims, insisting that small Greek islands near the Turkish coast should not be taken into account when delineating maritime boundaries.
Nato members Greece and Turkey are also at odds over migration and the division of Cyprus.
A Greek government spokesperson told reporters on Tuesday that Athens is monitoring the situation carefully.
"We need to be vigilant ... we've always done what we have to do to have stability in our region and to fully defend international law and our own sovereign rights," spokesperson Giannis Oikonomou said.
The first well to be visited by the Abdulhamid Han is 55 kilometres off the Turkish coast and in undisputed waters, Mr Erdogan said.
He brushed aside any objections by saying: "Neither the puppets nor the ones who hold their strings will be able to prevent us from getting our rights in the Mediterranean."
Turkey describes the 238 metre-long ship, which has a crew of up to 200, as a seventh-generation model capable of drilling to depths of more than 12 kilometres.
The launch comes with attention turning to a general election next year, at which Mr Erdogan will be up for re-election as president.
Mr Erdogan said the new drilling would help make Turkey less reliant on foreign energy imports. It separately discovered a natural gas reserve with a volume of 540 billion cubic metres in the Black Sea.
