The American president urged European nations including the UK, France and Germany to “take back” more than 800 jihadi militants as the US prepares to withdraw troops from the Middle East.
“The alternative is not a good one in that we will be forced to release them,” he tweeted. “The US does not want to watch as these Isis fighters permeate Europe, which is where they are expected to go.
“We do so much, and spend so much – Time for others to step up and do the job that they are so capable of doing.”
His warning came with US-backed forces poised to capture the last, tiny enclave of Isis’s once-sprawling proclaimed caliphate.
The Kurdish-led Syrian Democratic Forces (SDF) said on Saturday they had cornered the jihadi group in a 700-square-metre encampment in the village of Baghouz on the eastern banks of the Euphrates river.
“The caliphate is ready to fall,” said Mr Trump, who added the US would be “pulling back” after the last pocket of Isis territory is seized.
In December the president shocked allies and his own advisers by ordering the full withdrawal of 2,000 US troops from Syria.
“We have defeated Isis in Syria, my only reason for being there during the Trump presidency,” he declared at the time.
His position is at odds with his own US military chiefs, who warn the recapture of Isis territory does not mean the group has been vanquished.
SDF battle commander Jiya Furat said his forces would move onto “chasing down sleeper cells and remnants spread out across the region” after seizing control of Baghouz.
The swift withdrawal of US troops from Syria could also have a potentially destabilising effect in the north and east of the country, where Kurdish forces have beaten back Isis and maintained a degree of order with American backing.
Mr Trump’s plea for allies to repatriate and prosecute captured jidahis came amid confusion over the fate of a British teenager who fled to Syria to join Isis in 2015.
British home secretary Sajid Javid has vowed he “will not hesitate” to prevent 19-year-old Shamima Begum returning to the UK, but justice secretary David Gauke conceded the government “can’t make people stateless”.
Ms Begum, who is heavily pregnant, is currently in a Syrian refugee camp but has said she wants to return to London.
The teenager is believed to be one of 20 UK women and children being held in camps by the SDF along with six suspected British fighters.
Kurdish officials have urged the UK to fulfil its “moral and legal duty” to repatrirate British Isis members.
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