A woman who was stripped of her British citizenship after joining the Islamic State group in Syria will on Wednesday find out if she has won her legal battle to reverse the decision.

Shamima Begum, now 23, was aged 15 in 2015 when she left her home in east London with two school friends to travel to Syria. While there she married an IS fighter and had three children, none of whom survived.

Then-interior secretary Sajid Javid revoked her British citizenship on national security grounds after she was found in a Syrian refugee camp in February 2019, leaving her stateless.

Begum is one of hundreds of Europeans whose fate following the 2019 collapse of the Islamist extremists’ self-styled caliphate has proved a thorny issue for governments.

The UK Supreme Court last year refused her permission to enter the UK to fight her citizenship case against the interior ministry, and she has now taken the case to the Special Immigration Appeals Commission (SIAC).

Begum’s lawyer, Samantha Knights, told the five-day SIAC hearing in November that “at its heart this case concerns a British child aged 15 who was… influenced… with her friends… by a determined and effective Isis propaganda machine”.

There was “overwhelming” evidence she had been “recruited, transported, transferred, harboured and received in Syria for the purposes of ‘sexual exploitation’ and ‘marriage’ to an adult male”, she added in written submissions.

The process by which the government took the decision to remove Begum’s citizenship was “extraordinary” and “over hasty”, she added.

James Eadie, for the government, however said Begum “travelled, aligned, and stayed in Syria for four years” and that she only left IS-controlled territory for safety reasons “and not because of a genuine disengagement from the group”.

Javid “properly considered” all the factors before making his decision; the case was about “national security”, not trafficking, he added.

Begum’s apparent lack of remorse in initial interviews drew outrage, but she has since expressed regret for her actions and sympathy for IS victims.

In a documentary last year, she said that on arrival in Syria she quickly realised IS were “trapping people” to boost the caliphate’s numbers and “look good for the (propaganda) videos”.

Some 900 people are estimated to have travelled from Britain to Syria and Iraq to join IS. Of those, around 150 are believed to have been stripped of their citizenship.

Judge Robert Jay is expected to issue the decision on Begum’s case at 1000 GMT.