ISTANBUL — In the face of menacing warnings from Turkey on Monday, the Greek Cypriot government said it was proceeding with exploratory drilling for oil and gas off the coast of the disputed island.

Turkey called the wells an act of provocation, and Prime Minister Recep Tayyip Erdogan said in a televised statement that Turkish “frigates, gunboats and its air force will constantly monitor developments in the area.” He later added that Turkey would start its own seismic exploration program in the area, the site of major natural gas deposits claimed largely by Israel.

Cyprus has been divided since 1974 into an internationally accepted Greek Cypriot south and a Turkish Cypriot north that is recognized only by Turkey. While the Greek Cypriots say the drilling is taking place south of the island, in their exclusive economic zone, Turkish officials do not accept the Greek Cypriots’ claims to the area.

“We have different attitudes for the region that they have declared as an exclusive economic region,” Mr. Erdogan said. “This is a disputed exclusive economic region, and we have earlier conveyed to them that taking such a step in this disputed region would be incorrect.”