Egypt, Cyprus, and Greece have condemned plans by Turkey to explore for oil inside Cyprus waters, terming them “unlawful and unacceptable”.

Egyptian President Abdel Fattah el-Sisi hosted Cypriot President Nicos Anastasiades and Greek Prime Minister Kyriakos Mitsotakis in Cairo for talks, after which they said Turkey’s plan was “a breach of international law”.

“The Heads of State and Government expressed their grave concern over the current escalation within the maritime areas of the eastern part of the Mediterranean, condemning the continuing Turkish actions in the exclusive economic zone of Cyprus and its territorial waters, in violation of international law,” said a joint statement from the three leaders.

President el-Sisi said Turkey’s plan risked destabilizing the whole eastern Mediterranean, fears shared earlier in the year by Greece.

The three leaders also took the opportunity to condemn Turkey’s planned military offensive into northeastern Syria following an announcement by the U.S. that it was withdrawing its troops to allow a Turkish attack on Syrian Kurdish fighters.

U.S. troops “will not support or be involved in the operation” and “will no longer be in the immediate area” in northern Syria, White House press secretary Stephanie Grisham said in a statement on Sunday.

There are about 1,000 U.S. troops in northern Syria.