Shamima Begum, a teenager who left London to join the IS terror group in Syria, has had her UK citizenship revoked.
The decision against the 19-year-old comes after she expressed her desire to return to the UK with her newly-born child in a media interview.
Her family's lawyer said they were considering "all legal avenues" to challenge it.
Home Secretary Sajid Javid has said he would “not hesitate” to prevent the return to Britain of anyone who has supported terrorist organizations aboard.