The Turkish army conducted the test firing of the S400 missile defence system in the northern province of Sinop by the Black Sea, according to the pro-government television station A Haber.

Other Turkish media have shared an amateur video showing a white streak in the sky.

The defence ministry refused to confirm or deny the test firing.

Turkey's acquisition of the S400s has caused friction with the West which says they are not compatible with NATO systems.

Turkey has been a member of NATO since 1952.

In response to the delivery of the first battery last year, the United States suspended Turkey from the production programme of F-35 fighter jets.

Washington also threatened Ankara with sanctions if the S400s were activated.

Despite repeated warnings, President Recep Tayyip Erdogan has repeatedly asserted that the S400s will be deployed.

Ankara defends itself by asserting that the United States refused to sell it the competing American Patriots.