The government sought to maintain a low profile yesterday after Greek defense officials reported that a Turkish marine research ship had reappeared in Greece’s continental shelf area in the northern Aegean, the stretch of seabed where Athens claims the rights for exploration and exploitation of potential mineral and fossil fuel deposits. But Foreign Ministry officials told Kathimerini that the movements of the Cesme, and the reappearance of the Piri Reis, another Turkish research vessel, near Kastellorizo, in the southern Aegean, had riled Athens and did not bode well for the progress of exploratory talks aimed at resolving bilateral disputes in the Aegean. «It is clear that the Turks are trying to maintain tension but we will not play their game because, the way we see it, is they that will have to justify their provocative actions,» a close aide to Alternate Foreign Minister Dimitris Droutsas told Kathimerini. The same source remarked that Greece’s passive stance vis-a-vis Turkey was part of a «well-coordinated strategy,» adding that Greek diplomats would set out their position regarding the delineation of the continental shelf during negotiations with their Turkish counterparts currently under way in Istanbul. The source concluded that Athens had «more diplomatic tools» to resort to if Ankara continued its provocative behavior. Greek defense officials said yesterday that the Cesme, the Turkish marine research ship, has been off the coast of Thrace, close to the island of Samothrace, since late on Monday. Meanwhile, authorities said they were closely following the movements of the Piri Reis, which reappeared near Greek territorial waters close to Kastellorizo in the southern Aegean on Sunday for the second time in as many weeks. In a related development, four Turkish fighter jets violated Greek air space yesterday afternoon by flying over the small Aegean island of Agathonisi before being chased off by Greek aircraft. Greek defense officials said it was the fourth such transgression by Turkish aircraft in three weeks. In the six months prior to that, only three such violations had been reported.