Canada said on Sunday it was disappointed the United Kingdom had decided to "off-load their responsibilities" after its close ally revoked the citizenship of an Isil fighter known as Jihadi Jack.

Muslim convert Jack Letts, 24, who had held dual UK and Canadian citizenship, declared he was an "enemy of Britain" after travelling from Oxfordshire to Syria at the age of 18 to join the Islamic State of Iraq and the Levant.

He has begged to be allowed to return to the UK from Syria, insisting he had "no intention" of killing Britons, after he was captured by Kurdish forces in 2017.

The Home Office has now stripped Letts of British citizenship, meaning he is the responsibility of the Canadian government, The Mail on Sunday said.

Canadian Public Safety Minister Ralph Goodale confirmed in a statement that Letts had been stripped of his British citizenship.

"Canada is disappointed that the United Kingdom has taken this unilateral action to off-load their responsibilities," Goodale said.