Speaking at a press conference where he announced the death of Isis leader Abu Bakr al-Baghdadi, the US president called European nations a “tremendous disappointment”.
After thanking Russia, Turkey, Syria and Iraq for assistance in the operation, Mr Trump said he had personally pressured EU countries to take back Isis members.
“They came from France, they came from Germany, they came from the UK. They came from a lot of countries,” he added.
“And I actually said to them, if you don’t take them, I’m going to drop them right on your border and you can have fun capturing them again.”
Mr Trump suggested that if detainees escape Kurdish-controlled camps, the US will not “capture people that want to go back to Germany, France, UK and other parts of Europe”.
“They could walk back – they can’t walk to our country. We have lots of water in between our country and them,” he added.
Mr Trump has made similar threats several times in the past, saying earlier this month that he was unconcerned over the potential escape of Isis fighters because “they’re going to be escaping to Europe”.
In August, the US president claimed he would “release [thousands of Isis fighters] to Europe” if they were not repatriated, but the threat has never materialised.
The US does not directly control the prisons and camps where foreign fighters, female Isis members and their children are being held by Kurdish forces.
Numerous escapes have been reported since Mr Trump ordered the US military to withdraw from Syria earlier this month, sparking a Turkish-backed incursion into the areas where Isis members were detained.
Divisions between the captives have also sparked assassinations and unrest inside the camps, amid warnings of a potential Isis insurgence.
In the last audio message released before his death, Baghdadi directly called for his followers to free detained Isis members and their families from camps.
Dozens of jihadis from the UK and at least 60 British children who fled Isis-held areas as the group’s “caliphate” fell are thought to be held in northern Syria, including Shamima Begum and Jack Letts.
Two members of the British Isis terror cell known as “The Beatles” have already been transferred to US custody for trial over the torture and execution of hostages including James Foley and David Haines.
Kurdish commanders in the region have told The Independent they cannot secure Isis prisons and camps if fighting with Turkish forces continues in spite of a Russia-brokered ceasefire.
“We are still maintaining control but if the Turkish threat and attacks continue, we do not know for how long we will be able to keep these prisons secured,” said Syrian Defence Forces commander Mervan Qamishli.
“We need help stopping the conflict so that our forces can return to protecting and managing the prisons.”
American officials say that at least 100 Isis fighters have already escaped in the two weeks since Turkey launched its incursion against Kurdish fighters, which were allied to the US-led coalition but considered terrorists by Ankara.
Kurdish officials estimate that an additional 800 Isis family members may have also fled from Ain Issa camp, which was home to more than 100,000 displaced people.
There are also fears over the security of the al-Hol and Roj camps, which are each home to significant populations of foreign Isis suspects.
The British government has refused to repatriate captives for trial and dramatically increased its use of controversial citizenship deprivation powers to prevent any return to the UK.
Reports suggest it may be preparing to transfer children of British jihadis who have been trapped in the warzone, although it is unclear whether the policy would only apply to unaccompanied children and orphans, or those still with their parents.
Several MPs have called for the government to repatriate UK extremists, which Kurdish officials called Britain’s “moral and legal duty”.
In August, former defence minister Tobias Ellwood warned that the detention of thousands of jihadis and their families in Syria was creating conditions for an Isis resurgence and global terror attacks.
“We’ll see Daesh 2.0,” he told The Independent. “We’ll see a repeat of al-Qaeda regrouping and becoming a very real threat, and that threat won’t just pose itself in the Middle East, but also to Britain.”
The government welcomed news of Baghdadi’s death on Saturday but experts said that Isis’s bureaucracy and increased focus on international factions outside Iraq and Syria would ensure its survival.
Before becoming the “caliph” of the self-declared Islamic State during a 2014 advance, where it waged a campaign of genocide, mass rape and forced against the Yazidi minority, Baghdadi had been captured by US forces.
He was detained in the Iraqi city of Fallujah in 2004 alongside other extremists who would become senior Isis figures.
He became the leader of al-Qaeda in Iraq in 2010 – a year before the death of Osama bin Laden – and waged a bloody terrorist campaign in the country before expanding into Syria and declaring the formation of Isis following infighting in 2014.
Mr Trump said Baghdadi killed himself and three children by detonating a suicide bomb during a US special forces raid on his Syrian hideout on Saturday.
The Independent understands that the British military was not involved in the operation.
Boris Johnson called Baghdadi’s death “an important moment in our fight against terror” but added: “The battle against the evil of Daesh is not yet over.
“We will work with our coalition partners to bring an end to the murderous, barbaric activities of Daesh once and for all.”