Turkish President Tayyip Erdogan said Turkey was aiming to reinforce its troops deployments in its Iraqi border town of Silopi and that it would have a "different response" for Shi'ite militia groups if they cause terror in the Iraqi city of Tal Afar.

Iranian-backed Iraqi Shi'ite paramilitary groups have said they have started an offensive against Islamic State positions west of Mosul, which will target Tal Afar.

Speaking to reporters at a reception marking Republic Day in Ankara, Erdogan said the information he received had not confirmed such movement. He gave no details on the numbers of reinforcements, or what the different response would be.

Ankara has repeatedly warned that it would take measures if there is an attack on the city, which has a sizeable ethnic Turkmen population, as part of a wider US-led offensive to retake Iraqi city of Mosul from Islamic State.