The Greek navy said nobody was hurt in the collision late on Monday, the second such incident in a month, which it blamed on "dangerous manoeuvres" by the Turkish boat.

However, the Greek vessel suffered damage.

The incident occurred near the uninhabited Imia islets, just off the Turkish coast and a historic flashpoint in a long-running demarcation dispute.

A similar incident had occurred last month. At that time, the Greek navy said the two vessels' sides "came together...probably owing to an error on the part of the Turkish vessel."

It came as EU President Donald Tusk on Tuesday urged Turkey to "avoid threats or actions against any EU member" after Turkish warships blocked an Italian drilling vessel seeking to begin exploration for gas off Cyprus.

President Recep Tayyip Erdogan then warned foreign energy companies not to "overstep the mark" in the Mediterranean.

Greek government spokesman Dimitris Tzanakopoulos said Athens was "troubled" by Turkey's behaviour.

"There is tension in Turkey, problems that Mr Erdogan and his government are having trouble dealing with, and a general destabilisation in the area surrounding Turkey," Tzanakopoulos told Alpha radio.

"(Turkey) is not helping to smoothe out the turbulence, it's doing the opposite," he said.

The Imia islets -- called Kardak in Turkey -- lie just seven kilometres (4.5 miles) from the Turkish port of Bodrum.

A row over their sovereignty flared in January 1996, when the two countries sent marines to two neighbouring islands in a sign of an imminent armed confrontation.

They then withdrew their troops after heavy diplomatic pressure by the United States, a fellow member of NATO.