Ankara is to order a further 24 Lockheed Martin F-35 aircraft, Turkish Defense Minister Fikri Isik said in an interview with broadcaster A Haber on Tuesday.

Turkey is expected to receive the stealth fighters in 2018.

According to sources, Ankara plans to acquire 116 F-35s to replace its fleet of F-16 jets.

The news has caused unease in Athens in the wake of a string of provocative statements by Turkish President Recep Tayyip Erdogan relating to the sovereignty of Greek islands.