The Home Secretary has warned he “will not hesitate” to prevent the return of Britons who travelled to join Islamic State as debate flared over what should happen to runaway Bethnal Green schoolgirl Shamima Begum.

East London Advertiser: Shamima Begum wants to return to the UK. Pic: Met PoliceShamima Begum wants to return to the UK. Pic: Met Police (Image: MPS)

Sajid Javid said those who left the UK to join IS were “full of hate for our country”, while the Security Minister, Ben Wallace, warned that runaways who now want to come back must realise that “actions have consequences”.

Ms Begum’s family has pleaded for the 19-year-old, who is heavily pregnant, to be shown mercy and to be allowed to return home.

Speaking to The Times at a refugee camp in northern Syria, Ms Begum said she would “do anything required just to be able to come home and live quietly with my child”.

Her case has received high-profile backing, with a former MI6 chief saying the teenager should be given a chance “if we are to stand by our values”.

But her plea has been strongly rejected by others - including the brother of Alan Henning, the British aid worker beheaded by Jihadi John, who said she should “absolutely not” be allowed back.

Mr Javid said: “We must remember that those who left Britain to join Daesh were full of hate for our country.

“My message is clear - if you have supported terrorist organisations abroad I will not hesitate to prevent your return. If you do manage to return you should be ready to be questioned, investigated and potentially prosecuted.”

Any hopes of a rescue mission by British officials were swiftly quashed yesterday as the government ruled out an effort inside Syria to assist Ms Begum.

While refusing to comment on individual cases, Mr Wallace told the BBC: “I’m not putting at risk British people’s lives to go and look for terrorists or former terrorists in a failed state.

“There’s consular services elsewhere in the region and the strong message this government has given for many years is that actions have consequences.”

While no official operation to remove Ms Begum from Syria will be carried out, questions have been raised over whether Britain would be able to prevent Ms Begum’s eventual return to the UK.

The former independent reviewer of terrorism legislation, Lord Carlile, said that if Ms Begum has not gained a second citizenship of another country she will have to be allowed back to her homeland because under international law it is not possible for a person to be made “stateless”.

Meanwhile, Richard Barrett, a former director of global counter-terrorism at MI6, suggested it would be “unreasonable” to expect the Syrian Defence Force to look after her indefinitely.

He also warned that summary execution is the “most likely outcome” for such captured foreign nationals who are handed over to Syrian or Iraqi authorities.

Ms Begum’s admission that she did not regret travelling to IS-controlled Syria, and her assertion that she is “not the same silly little 15-year-old schoolgirl who ran away from Bethnal Green four years ago” has been highlighted as a cause for concern by some.

Dr Kim Howells, a former counter-terrorism minister, said: “She sounds to be completely unrepentant, she sounds cynical.”

Mr Henning’s brother, Reg, said: “The authorities should take her passport off her. She made her choice, didn’t she? She made her bed and she should lie in it.”

However, Ms Begum’s brother-in-law Mohammed Rehman said that her family want her to be allowed to return and be “re-educated”.

He said: “I can understand why people in this country are angry and don’t want her back. What she’s done doesn’t portray Islam in a good light. But she was only 15 when she went to Syria. We are appealing for compassion and understanding on her behalf.”

Ms Begum was one of three schoolgirls, along with Kadiza Sultana and Amira Abase, from Bethnal Green Academy who left the UK in February 2015.

Another girl, Sharmeena Begum, also from Bethnal Green but not related to Shamima, had travelled to Syria two months earlier.

Ms Sultana was reported to have been killed in an air strike in 2016.

Shamima Begum said she had recently heard second-hand that the other two girls may still be alive.