ANKARA: A Turkish research ship at the centre of a row with Greece over potential gas riches in the eastern Mediterranean has returned to port, Turkey's energy ministry said Monday. The Oruc Reis seismic survey vessel has become a symbol of Turkey's growing appetite to find natural gas in the contested waters despite opposition by Greece and Cyprus.

Backed by Turkish navy frigates, the ship was first deployed in August and again in October to the waters south of Greece's Kastellorizo island, in defiance of calls to stop by the European Union and the United States. Ankara says that with its long Mediterranean coastline, its claim to sovereign waters in the region is stronger than Greece's, which is based on the tiny island of Kastellorizo.

"Our ship has completed its two-dimensional seismic research in the Demre area which began on August 10... and has now returned to Antalya port" in southern Turkey, the energy ministry tweeted. The ship collected "10,995 kilometres" (7,000 miles) of data, it said.