The United States and its allies launched airstrikes on the Iraqi city of Tikrit, the Defence Department said late Wednesday, in support of an Iraqi government offensive to retake the northern city from the radicals.

The operation by the US-led coalition had been requested by Prime Minister Haider al-Abadi, the US said.

The strikes would target only Islamic State forces and would avoid civilian casualties or damage to infrastructure where possible, commanding General James Terry said.

“This will further enable Iraqi forces under Iraqi command to manoeuvre and defeat [Islamic State radicals] in the vicinity of Tikrit,” Terry said.

Iraqi and allied forces are in the middle of an offensive to retake the city, comprising more than 20,000 fighters, mostly thought to be Shiite militias backed by Iran.

“We do not coordinate our operations in any way with Iran or Iranian-backed militias,” Terry said.

The militias have vowed revenge for the apparent mass execution of up to 1,200 Shiite army recruits by Islamic State forces during the lightning offensive last June that saw the radicals seize Tikrit, Iraq’s second city of Mosul, and other mainly Sunni areas. SAPA