The United States is planning to send British Isil fighters to Guantánamo Bay amid frustration at the UK’s failure to take responsibility for its homegrown terrorists, The Telegraph can reveal.

Senior US officials believe Guantánamo can house more than 50 Islamic State of Iraq and the Levant fighters, including the two surviving British members of the so-called “Beatles” terrorist cell that executed Western hostages.

It has emerged that the vast majority of Islamist fighters returning to the UK from Syria have been placed on “secretive” government rehabilitation schemes rather than be prosecuted.

Official figures show only one in 10 jihadists have been prosecuted.

The row over the treatment of returning jihadists erupted on Thursday after it emerged that a former schoolgirl who joined Isil in 2015 is now languishing in a refugee camp and pleading to come back to the UK.

The Home Office minister in charge of security declined Shamima Begum’s plea to be rescued, insisting that her “actions have consequences”.