After a joint search and rescue operation with Syria, "it has been understood that our plane has been struck down by Syria," Prime Minister Recep Tayyip Erdogan said in a written statement after leading an emergency meeting of top military and government figures.

Erdogan also said "Turkey will announce its final position and take necessary steps with determination after the incident is entirely clarified," without further elaborating on possible retaliatory measures.

The jet had lost radio contact with its base over the eastern Mediterranean near Syria's Latakia, an army statement said earlier.