Iraq has begun an aerial bombardment of Tal Afar, a town under Islamic State (IS) militants control west of Mosul, Baghdad-based al-Sumariya TV said on Tuesday, citing an Iraqi Defence Ministry spokesman.

The ground attack to try to take the city should start when the air campaign is over, the spokesman, Mohammed al-Khodari, said, according to the TV channel.

Iraqi authorities had said Tal Afar, 80 km (50 miles) west of Mosul, will be the next target in the war on the Islamist militant group that swept through swathes of Iraq and Syria in 2014.

IS self-proclaimed "caliphate" effectively collapsed last month, when U.S.-backed Iraqi forces completed the recapture of the militants' capital in Iraq, Mosul, after a nine-month campaign.

Tal Afar, which had about 200,000 residents before falling to Islamic State (IS) militants, experienced cycles of sectarian violence between Sunnis and Shias after the U.S.-led invasion of Iraq in 2003, and has produced some of IS most senior commanders.