ATHENS, Greece (AP) — Greece said Monday that it will conduct a navy and air force exercise in an area of the eastern Mediterranean where Turkey is prospecting for oil and gas in an area as the neighboring countries remain locked in a dispute over offshore energy rights.

Authorities said t the live-fire exercises would start Tuesday southeast of the Greek island of Crete and end Thursday.

Turkey has a research ship escorted by warships surveying for oil and gas exploration in the area and said Sunday that the work would continue through Aug. 27.

The Turkish government disputes Greece’s claim to exclusive rights in the waters where the research vessel is working, arguing that islands should not be included in calculating sea boundaries between countries.

The United States and the European Union so far have backed Greece i the dispute. .

German Foreign Minister Heiko Maas is due in Athens and Ankara on Tuesday to try and revive deescalation talks between senior Greek and Turkish officials, an initiative started in July but broken off by Turkey several weeks later.