Shamima Begum has lost a Court of Appeal decision to regain her UK citizenship.
The ruling means the 24-year-old remains barred from returning from Syria. The UK government stripped her of her British citizenship on national security grounds in 2019.
Ms Begum left her home in London to travel to Syria and join Islamic State group, or IS, nine years ago aged 15.
She lost a previous challenge last year against the Home Office’s decision.