Mattis: US to fight Islamic State in Syria 'as long as they want to fight'

WASHINGTON – The US military will fight Islamic State in Syria "as long as they want to fight," Defense Secretary Jim Mattis said on Monday, describing a longer-term role for US troops long after the insurgents lose all of the territory they control.

As US-backed and Russian-backed forces battle to retake the remaining pockets of Islamic State-held terrain, Mattis said the US military's longer-term objective would be to prevent the return of an "ISIS 2.0."

"The enemy hasn't declared that they're done with the area yet, so we'll keep fighting as long as they want to fight," Mattis said, speaking to reporters at the Pentagon about the future of US operations in Syria.

He also stressed the importance of longer-term peace efforts, suggesting US forces aimed to help set the conditions of a diplomatic solution in Syria, now in its seventh year of civil war.