WASHINGTON, D.C.—The U.S. State Department on July 9 urged Turkish authorities to halt energy drilling operations off the Cypriot coast in the Mediterranean, a day after Cyprus protested a Turkish ship dropping anchor there.

"This provocative step raises tensions in the region. We urge Turkish authorities to halt these operations and encourage all parties to act with restraint and refrain from actions that increase tensions in the region," a U.S. State Department spokeswoman said in a statement.

Turkey and the internationally recognized government of Cyprus have overlapping claims in that part of the Mediterranean, an area thought to be rich in natural gas.

Cyprus, a member of the European Union, has discovered natural gas in areas off the southern coast of the disputed island, though nothing has been extracted. Turkey contests the rights of Cyprus to explore for gas, sending its own drilling ships to stake claims around the island.

Refinitiv Eikon shipping data showed a Turkish ship arrived off the east coast of Cyprus earlier this week. Another Turkish vessel has been spotted off the west of Cyprus since early May.

The Cypriot presidency on Monday accused Turkey of a "grave violation," and an EU statement also rebuked the Turkish action.

Cyprus was divided in 1974 after a Turkish invasion triggered by a Greek-inspired coup. Several peacemaking efforts have failed and the discovery of offshore resources has complicated the negotiations.