The letter addressed to Begum's mother included:
"According to the Interior Ministry's decision, your daughter was deprived of her British citizenship," it said, adding that the family had the right to appeal the sentence if it wanted that.
"The Begum family was very disappointed by the decision of the Interior Ministry," the newspaper quoted Tasnim Akunji, the family's lawyer, as saying. "We are studying all legal means to challenge the decision."
Akunji said that Begum only had a British passport and did not has a Bengali travel document, while the interior replied that it "does not strip people of citizenship", noting that " Begum family is of Bangladeshi origin."
Shamima joined IS mercenaries four years ago and married a Dutch mercenary.
After her husband was arrested and then killed, she fled to a refugee camp in northern Syria where she gave birth to her only child.
The argument that accompanied her calls for return is that, during her meeting with The Times Newspaper, she did not express her remorse for joining IS, which probably led to her citizenship denial. Even though she revealed "IS" reality with regard to corruption and repression "which she no longer tolerates."
On the other hand, the father of the girl, Abbas Hussein, criticized the British authorities, saying that they did not cooperate with his family to return his daughter.