The IS fighter known as Jihadi Jack has been stripped of his British citizenship, sparking a furious diplomatic row with Canada.

Muslim convert Jack Letts, 24, had held duel UK and Canadian citizenship but declared himself an ‘enemy of Britain’ after fleeing his Oxfordshire home to fight in Syria.

After being captured by Kurdish authorities, he begged to be allowed back to the UK and, despite previously saying he wanted to be a suicide bomber, insisted he had ‘no intention of blowing up’ Britons.

Jihadi Jack has been stripped of his British citizenship by the Home Office, sparking a row between the UK and Canada, where he is also a citizen

Muslim convert Jack Letts, 24, fled from his Oxfordshire home to fight for IS in Syria and has declared himself an 'enemy of Britain'. He was captured and jailed by forces fighting the Islamic State group in 2017

But The Mail on Sunday can reveal that the Home Office has torn up his British passport, making him the responsibility of the Canadian government.

The decision has sparked fury in Ottawa, with fears of a public spat when Canadian PM Justin Trudeau meets Boris Johnson at the G7 summit in France next weekend.

Whitehall officials suspect the row may also explain the recent hardline stance taken by the Canadians over a post-Brexit trade deal with the UK.

Despite being close allies, there was surprise last month when the Trudeau administration said it would not automatically ‘roll over’ the trade deal it has with the European Union for the UK.

A diplomatic source said the Canadian government had ‘gone berserk’ at the decision to remove Letts’s UK citizenship because he had ‘very little to do with Canada’.

But a Whitehall insider last night hit back, saying: ‘It’s Canada’s problem now.’

Sally Lane and John Letts, who is Canadian, sent £223 to their son while he was in Syria despite learning he had joined IS. They were convicted of funding terrorism. (Pictured: Sally Lane and John Letts)

Ottawa is said to have 'gone berserk' when it heard about Letts being stripped of his citizenship, and is thought to be the reason Canada has taken a hardline in post-Brexit trade deal negotiations. (Pictured: Letts in an image released by Counter Terrorism Policing South East)

A Whitehall source is understood to have said that Letts is 'Canada's problem now'. (Pictured: Letts in a family picture released this year)

Letts is among more than 120 dual nationals who have been stripped of their British citizenship since 2016. International law prevents the Government from making people ‘stateless’ so the move can only be taken against those with two passports.

After converting to Islam at 16, Letts travelled to the Middle East in 2014, where he married an Iraqi woman. He was captured and jailed in 2017 by forces fighting IS.

The Mail on Sunday understands the decision to revoke Letts’s citizenship was one of the last actions of Theresa May’s administration, led by Sajid Javid.

But Home Office sources said the decision was supported by Home Secretary Priti Patel and would not be changed.

An insider said: ‘It is Priti’s job to keep the country safe and she will do whatever is in her power to keep terrorist fighters out of the UK, including depriving dual nationals of their British citizenship when it is legal to do so and the intelligence shows there is a threat.’

The news is a devastating blow to Letts’s parents, who were found guilty at the Old Bailey in June of funding terrorism. They were sentenced to 15 months imprisonment, suspended for 12 months.

Letts is among more than 120 dual nationals who have been stripped of their British citizenship since 2016. (Pictured: Letts with his father John, who is Canadian)

The Mail on Sunday understands that it was one of the last actions of Theresa May's administration. Diplomatic sources have said it may be the reason that Canada has taken a hardline stance over a post-Brexit trade deal. (Pictured: His parents were convicted of funding terrorism after sending their son money)

Sally Lane and John Letts, who is Canadian, sent £223 to their son while he was in Syria despite learning he had joined IS.

In an interview after their conviction, they said: ‘Jack is still a British citizen and we have pleaded with the Government to help us to bring him to safety, even if that meant that he might be prosecuted in the UK. If there is evidence he has committed a crime then he should be tried.’

Since the court case, Letts has repeated his wish to return to Britain and condemned the decision to prosecute his parents.

‘I understand I am being punished because of what I have done but my mother shouldn’t be punished for that,’ he said.

‘They didn’t do anything wrong. They sent me money to leave [IS] ... I really want to see them, more than I have in my whole life.’

A Home Office spokesman said: ‘Decisions on depriving a dual national of citizenship are based on substantial advice from officials, lawyers and the intelligence agencies and all the available information. This power is one way we can counter the terrorist threat posed by some of the most dangerous individuals and keep our country safe.’

Letts’s parents declined to comment yesterday and the Canadian Government last night also declined to comment.