Concerns are growing there could be a conflict between Turkey and Greece in the eastern Mediterranean.
For weeks, the two neighbouring countries have been disputing maritime boundaries and offshore energy rights.
On Tuesday, they sent warships to the waters in a show of force.
Turkey's vessel Oruc Reis is conducting research - and Greece says it is above its continental shelf.
Ankara disputes Athens' exclusive rights in the region.
Both countries have announced military exercises within a broad area between the Greek island of Crete and Cyprus.
But they have also signalled readiness for dialogue as Germany tries to mediate between the NATO allies.
So, could this dispute escalate? And what would it take to defuse it?
Presenter: Adrian Finighan
Guests:
George Tzogopoulos - Strategic affairs analyst and lecturer at the Democritus University of Thrace
Wolf Piccoli - Managing director of the political risk arm of global adviser Teneo
Yusuf Alabarda - Retired Turkish colonel and security analyst at the Turkish Defence University
