As ISIS fighters flee west toward Damascus, US-led coalition won't follow to fight them British general says the coalition will stay in partner force-controlled areas.

 -- With the collapse of the ISIS caliphate in 2017, what's left of the terrorist group in Iraq and Syria is on the run, with some fighters moving west toward Damascus into Syrian regime-controlled territory and away from where the U.S.-led coalition will work to defeat them.

A two-star British general in the coalition's war against ISIS confirmed the "movement of limited numbers of ISIS militants westwards," but said the U.S.-led coalition won't pursue them because the area is operated by the regime.

"The coalition will remain committed to the mission in Syria until ISIS no longer poses a threat and a [United Nations]-backed peace process is implemented to ensure lasting stability in the country," British Army Major Gen. Felix Gedney, deputy commander of strategy and support for the coalition, told reporters during a Pentagon briefing on Wednesday.

But he later clarified the coalition would only defeat ISIS "in areas controlled by partner forces," leaving the Syrian regime and their Russian backers to oust the ISIS fighters that have moved west.

Gedney, as well as U.S. military leadership, have long expressed doubt in the regime's desire and ability to fight ISIS.

"They seem to be moving with impunity through regime-held territory, showing that the regime is clearly either unwilling or unable to defeat [ISIS] within their borders," Gedney said Wednesday.

The coalition dealt a significant blow to ISIS in 2017, liberating 60,000 square kilometers of land once claimed by the terrorist group, which ruled large swaths of Iraq and Syria since 2014. The coalition estimates only about 1,000 ISIS fighters remain in that area.

Last week, British Prime Minister Theresa May declared ISIS had been "crushed." President Trump went even further, saying "we've won" in Syria and Iraq.

"I would say that we've had a very successful 2017 in the military campaign," Gedney said. "We haven't created a win; we've created an opportunity."

Trump took a victory lap on Twitter late Wednesday, tweeting about the success of his administration in the fight against ISIS. The president quoted an article from the conservative Washington Examiner and an infographic based on Defense Department numbers comparing Trump's success against ISIS versus his predecessor, Barack Obama.

“On 1/20 - the day Trump was inaugurated - an estimated 35,000 ISIS fighters held approx 17,500 square miles of territory in both Iraq and Syria. As of 12/21, the U.S. military est the remaining 1,000 or so fighters occupy roughly 1,900 square miles..” @jamiejmcintyre @dcexaminer pic.twitter.com/OgYEuDgzD2 — Donald J. Trump (@realDonaldTrump) December 28, 2017

“On 1/20 - the day Trump was inaugurated - an estimated 35,000 ISIS fighters held approx 17,500 square miles of territory in both Iraq and Syria. As of 12/21, the U.S. military est the remaining 1,000 or so fighters occupy roughly 1,900 square miles..” @jamiejmcintyre @dcexaminer pic.twitter.com/OgYEuDgzD2