Senior US adviser Brett McGurk called for anyone who fought for the terror cult to be killed on the battlefield as soldiers celebrated the liberation of their former de-facto capital Raqqa.
He warned anybody who came to the city to join the unholy jihad would die their following their involvement in the spread of the so-called caliphate.
Mr McGurk said: “Our mission is to make sure any foreign fighter who is here, who joined ISIS from a foreign country and came into Syria, they will die here in Syria,”
“So if they’re in Raqqa, they’re going to die in Raqqa.”
There are believed to be many British jihadis in the region, however it is unclear if they would return to face trial in the UK if they were taken alive.
Yesterday Donald Trump triumphantly declared ISIS could soon be wiped off the face of the earth as the terror group cowers after losing control of Raqqa.
The US President declared the end of the so-called caliphate to be “in sight” after the liberation of Raqqa.
It comes amid celebrations in Raqqa as Kurdish and Arab militias clear the city of the boobytraps set by ISIS following the complete annihilation of jihadi forces in the city.
President Trump said: “I am pleased to announce that the Syrian Democratic Forces, our partners in the fight against ISIS in Syria, have successfully recaptured Raqqa – the terrorist group’s self-proclaimed capital city.”
“With the liberation of ISIS’ capital and the vast majority of its territory, the end of the ISIS caliphate is in sight.”
There are still swathes of Iraq and Syria controlled by the jihadi network, as well as pockets of support in Egypt and Libya.
Meanwhile, affiliates are operating in Nigeria, Afghanistan and the Philippines and the threat of international terror remains heightened.
However, the liberation of Raqqa from the cruel caliphate has dealt a significant blow to ISIS as the group runs out of places to hide from the internationally supported campaign to wipe them off the planet.
President Trump added: “Together, with our allies and partners, we will support diplomatic negotiations that end the violence, allow refugees to return safely home, and yield a political transition that honours the will of the Syrian people.”