A view of the al-Hol camp for internally-displaced people in northeastern Syria, where British-born Shamima Begum was discovered in 2019. Photo: Reuters / Khaled al-Hariri / File.

A British-born woman who went to Syria as a schoolgirl to join Islamic State can return to Britain to challenge the government’s removal of her citizenship, judges ruled on Thursday.

Shamima Begum, who was born to Bangladeshi parents, left London in 2015 when she was 15 and went to Syria via Turkey with two schoolfriends. In Syria, she married an Islamic State fighter and lived in the capital of the self-declared caliphate.

She was discovered in 2019 in a detention camp in Syria, where three of her children died. Britain stripped her of citizenship on security grounds as its domestic intelligence agency considered her a security threat.

But three judges from England’s Court of Appeal unanimously agreed Begum could have a fair and effective appeal of that decision only if she were permitted to come back to Britain.

“Fairness and justice must, on the facts of this case, outweigh the national security concerns,” judge Julian Flaux wrote in a ruling. “I consider that Ms Begum’s claim for judicial review of the decision of SIAC (Special Immigration Appeals Commission)… succeeds.”

The judge said that if Begum, who is now 20, was considered a security threat, and if there was sufficient evidence, she could be arrested on her return to Britain.

Begum angered many Britons by appearing unrepentant about seeing severed heads and saying a suicide attack that killed 22 people in the English city of Manchester in 2017 was justified.

She had pleaded to be repatriated to rejoin her family in London and said she was not a threat.

Britain’s Interior Ministry said the court’s decision was “very disappointing” and that it would apply for permission to appeal against it.

“The government’s top priority remains maintaining our national security and keeping the public safe,” an Interior Ministry spokeswoman said in a statement.