Cyprus said on Monday peace talks for the ethnically divided island could suffer if Turkey kept on opposing attempts by Nicosia to explore for gas off its southern coast, Reuters reported.
The internationally recognised Greek Cypriot government has licensed multinationals to explore for hydrocarbons in the area and Italy's ENI currently has a platform drill at one site.
Greek Cypriot officials said Ankara had issued a maritime advisory that a Turkish seismic vessel would be carrying out work in the same area as ENI's platform from Oct. 20.
Turkey, which backs a breakaway Turkish Cypriot enclave in northern Cyprus, does not recognise the jurisdiction of the Nicosia government in the exploration area.
"We consider this development particularly serious," Cypriot foreign minister Ioannis Kasoulides told a news conference in Nicosia. The area where ENI is carrying out the drill falls within Cyprus's exclusive economic zone, an area internationally recognised, except by Turkey, as being Cypriot waters, he said.
Cyprus, a member of the European Union, has become particularly keen to develop offshore gas reserves as a potential source of revenue since it was compelled to seek an international financial bailout in early 2013. Cypriot President Nicos Anastasiades has previously said challenges to the gas drills could trigger an interruption in the peace talks for the island.
Kasoulides said diplomatic and legal responses were being considered, but he declined to give details.
A US company, Noble, found an estimated 5 trillion cubic metres of gas south of Cyprus in late 2011, straddling a median line with Israel where major discoveries have been made in the past decade.
France's Total has also signed a concession to drill for gas with Cyprus.
Greek Cypriots say any hydrocarbon wealth discovered will be shared with the Turkish Cypriots in the event of a peace deal.
