Cyprus has launched legal proceedings against three firms that it accuses of supporting illegal Turkish oil and gas exploration in its waters, a foreign ministry official said Tuesday.
"We have already initiated legal proceedings against companies cooperating with the TPAO," an official at Cyprus's foreign ministry said, referring to Turkey's national energy firm.
The official said three companies and their executives were the subject of the legal action, without specifying the names or domiciles of the firms, or the jurisdiction where the complaint was filed.
The discovery of huge gas reserves in the eastern Mediterranean has fuelled a race to tap underwater resources and stoked long-standing tensions between EU member Cyprus and Turkey.
The island is divided between the internationally recognised Republic of Cyprus and a breakaway state set up after a 1974 Turkish invasion following a coup sponsored by the military junta then ruling Greece.
Cyprus had previously issued arrest warrants for the crew of a drilling vessel, the Fatih, which was deployed by Turkey to search for gas and oil in waters considered part of the EU state's exclusive economic zone (EEZ).
The Cypriot foreign ministry official said Tuesday that between 10 and 20 individuals, firms and executives were now subject either to arrest warrants or other legal action, including non-Turkish persons or entities.
All these actions were in relation to the deployment of the Fatih in Cyprus's EEZ, the official said, warning that similar action would be taken in the event of an anticipated breach by a second drill ship, the Yavuz.
The 229-metre-long (750-feet) Yavuz was deployed by Turkey on June 20.
Ankara considers much of the Cypriot-designated EEZ to be part of its continental shelf and granted exploration licences to Turkish Petroleum in 2009 and 2012.
But on June 20, the EU threatened sanctions against individuals and companies involved in Ankara's "illegal drilling activities".
The United States has also urged Turkey to reconsider its exploratory drilling plans off the island.
Energy giants Total of France and Italy's ENI are heavily involved in exploring for oil and gas off Cyprus as well as US giant ExxonMobil.