Islamic State hits back in Mosul but faces new Raqqa front

The jihadists have lost control of seven eastern districts of Mosul to Iraqi special forces who broke through their lines last Monday. Officials say the militants are now sheltering among civilians in those neighborhoods and targeting soldiers in what one called the world's "toughest urban warfare".

Mosul, the largest Islamic State-controlled city in either Iraq or Syria, has been held by the jihadist fighters since they drove the army out of northern Iraq in June 2014.

The three-week Mosul campaign has brought together a force of around 100,000 soldiers, security forces, Shi'ite militias and Kurdish fighters, backed by a U.S.-led coalition, to crush the Sunni jihadists.

Across the border, U.S.-backed Syrian fighters announced on Sunday the start of their own campaign, called Euphrates Anger, to recapture Islamic State's Syrian bastion of Raqqa.

The Syria Democratic Forces (SDF) is an alliance of Kurdish and Arab armed groups which has seized large swathes of territory along the Syria-Turkey border from Islamic State and pushed to within 30 km (20 miles) of Raqqa.

But the prominence within SDF ranks of the Kurdish People's Protection Units, or YPG, has raised questions over its suitability as a force to capture the predominantly Arab city.

Turkey, which has battled Kurdish separatists for three decades, regards the YPG as anathema and Western officials have said the Raqqa operation should be fought mainly by Arab forces.

Washington says the battle for Raqqa will "overlap" with the assault on Mosul, in part because of concerns that any delay would allow Islamic State to use it as a base to launch attacks on targets abroad.

France also wants a coordinated campaign against Islamic State in Iraq and Syria. "Mosul-Raqqa can't be disassociated because Islamic State and the territories it occupies span that area," Defence Minister Jean-Yves Le Drian said.