ANKARA (Reuters) - Turkey’s seismic exploration vessel Oruc Reis returned to port on Monday from disputed Mediterranean waters, less than two weeks before a European Union summit where the bloc will evaluate possible sanctions against Ankara. NATO members Turkey and Greece have conflicting claims to continental shelves and rights to potential energy resources in the eastern Mediterranean. Tensions flared in August when Ankara sent Oruc Reis to map out energy drilling prospects in waters also claimed by Greece. Turkey withdrew Oruc Reis from contested waters ahead of a previous EU summit in October to “allow for diplomacy”, but later sent it back after what it called unsatisfactory outcomes from the summit. Earlier this month, Turkey said Oruc Reis would operate in the region until Nov. 29. The energy ministry said on Monday the vessel had completed a mission which started on Aug. 10. “Our ship, which has collected 10,995 km of 2D seismic data, has returned to the Antalya port,” it said in a tweet. Refinitiv ship tracking data confirmed Oruc Reis was back in port in Antalya on Monday morning. The data also showed drill ship Yavuz in waters near Turkey’s southern coast, while seismic survey vessel Barbaros Hayreddin Pasa was still out at sea south of Cyprus. After weeks of tension, Ankara and Athens agreed to resume talks over their contested maritime claims in September, ending a 4-year hiatus. But Greece has since said it would not begin talks as long as Turkish vessels were in contested waters. Last week, the EU’s Parliament called for sanctions against Ankara over President Tayyip Erdogan’s visit to Northern Cyprus and Turkish operations in the eastern Mediterranean, which it called illegal. Turkey said it fully rejected this. EU leaders will meet on Dec. 11-12 to discuss the sanctions, with France leading a push in the bloc to sanction Turkey. Paris has yet to draw up sanctions, but diplomats say any measures would likely target areas of Turkey’s economy linked to hydrocarbon exploration.