(CNN) -- Turkey said Monday that Cyprus' decision to go ahead with exploratory oil drilling in the Mediterranean was a "provocation."
Houston-based Noble Energy began drilling Sunday night on the southern coast of Cyprus, according to the state-run Cyprus News Agency.
Turkish Energy Minister Taner Yildiz said his country would respond by doing drilling of its own, perhaps within the week. He said the drilling ship might be escorted by Turkish warships.
Last week, Cyprus called Turkey's plan to respond to Cypriot drilling as a provocation of its own.
The Republic of Cyprus maintains its sovereign rights in its continental shelf in accordance with international law, and no "agreement" or decision by Turkey will affect these rights," Cyprus' foreign ministry said in a statement on its website. "The Turkish announcement is yet another provocative act which is contrary to international law, both customary and conventional, and, in general to international norms."
Cyprus and Turkey have long battled over oil exploration and other issues.
Turkey invaded Cyprus in 1974 in response to a coup d'etat there engineered by Greece, which was then run by a military dictatorship. The island remains divided despite years of diplomatic efforts.
The southern portion of the island joined the European Union and is scheduled to take over the rotating presidency of that organization in 2012.
On Sunday, Turkey warned that it will freeze relations with the European Union, if Cyprus assumes the post.
Turkey is embroiled in a number of other regional issues, including over its relations with Israel and Syria.
U.S. Secretary of State Hillary Clinton met with Turkish Foreign Minister Ahmet Davutoglu in New York on Monday.
CNN's Yesim Comert contributed to this report.