Home Secretary Sajid Javid has fended off claims he has left IS bride Shamima Begum stateless by stripping her of her citizenship.
Speaking to ITV News' Peston he refused to comment on individual cases but said: "I would not take a decision - and I believe none of my predecessors ever have taken a decision - that at the point the decision is taken would leave that individual stateless."
Mr Javid's comments come as Bangladesh refused the 19-year-old, who gave birth on Sunday, dual citizenship.
ITV News Political Editor Robert Peston then asked Mr Javid what he thought of calls to bring the teenager back to face the UK's justice system.
He replied: "My number one job is to do whatever I can to keep this country safe and I admit that sometimes when you make these decisions they are not easy decisions.
"They can be very tough decisions, so many things to weigh up about the mortality of a decision, the legality of a decision, how it can have a huge impact on someone's life."
He added: "I have to go to bed at night and think 'have I done everything I could to keep this country safe?'"
In a statement on Wednesday, Bangladesh's ministry of foreign affairs said Ms Begum was not a Bangladeshi citizen and had never even visited the country.
Dhaka's reaction comes after Ms Begum was stripped of her British citizenship by the Home Office, a decision she told ITV News she found "kind of heart-breaking to read" and "hard to swallow".
But Bangladesh's government said it was "deeply concerned" that the 19-year-old had been "erroneously identified as a holder of dual citizenship".
"She is a British citizen by birth and has never applied for dual nationality with Bangladesh," the statement read.
"It may also be mentioned that she never visited Bangladesh in the past despite her parental lineage. So, there is no question of her being allowed to enter into Bangladesh."
Speaking to ITV News on Monday, the teenager insisted she was "not a threat" to the UK, despite having insisted she did not regret joining IS.
"I'm a 19-year-old girl with a newborn baby," she said..
"I don't have any weapons; I don't want to hurt anyone even if I did have weapons."