Shamima Begum’s bid to return to the UK was revived after European judges challenged Britain’s stance in the jihadi bride’s case.

The European Court of Human Rights (ECtHR) has formally told the Home Office to justify its decision to strip the ISIS fanatic of her British citizenship.

Ms Begum’s lawyers branded the move an “unprecedented opportunity” as it paves the way for a fresh clash between the UK and Strasbourg.

ECHR judges have asked the Government whether it broke human rights and anti-trafficking laws, Ms Begum’s key legal argument.

Shadow Justice Secretary Robert Jenrick told the Daily Express: “Under no circumstances should Shamima Begum ever step foot in the UK again. She chose to get into bed with ISIS terrorists and must now live with the consequences.

“We don’t need a foreign court in Strasbourg to tell us who can or can’t come into this country. This is yet another glaring example of why we must leave the ECtHR and take back control of our borders.”

Former Security Minister Sir Ben Wallace, who was part of the citizenship deprivation case for the Home Office, told the Daily Express: “She went of her own free will to support a cause that doesn’t believe in any Western court.

“She wasn’t a victim. She knowingly and freely joined ISIS and assisted them in the prosecution of their murderous campaign.

“She deserved to lose her citizenship.

“The cheek of her going through a court system that she and the other terrorists would fundamentally want to destroy isn’t lost on anybody.

“She wanted to go there. She can stay there.”

The formal “communication” between the ECtHR and Home Office will reignite fears Begum could eventually be allowed to travel back to the UK.

It signals that Strasbourg believes Ms Begum’s human rights may have been breached. Many cases submitted to the court are thrown out before they reach this stage.

Begum was born and raised in Bethnal Green, east London, before travelling to Syria aged 15 with two other school friends to join IS in 2015.

She later became a child bride to Dutch Islamic convert Yago Riedijk, with whom she had three children who all died as infants.

In 2019, the then home secretary Sajid Javid stripped her of British citizenship on the basis that she could also claim citizenship in Bangladesh so would not be stateless – a decision later upheld by the UK’s Supreme Court.

Now 26, Begum is still living in the al-Roj camp, which is home to thousands of former jihadis, after losing all of her appeals in the UK.

Birnberg Peirce Solicitors, which represents the ISIS bride, described the ECHR’s intervention as an “unprecedented opportunity”.

The Home Office has been told to answer – within months – four questions about its handling of Begum’s citizenship.

One asks: “Has there been a violation of the applicant’s rights under Article 4 of the Convention by virtue of the decision to deprive her of her citizenship?”

And the ECtHR hinted they are concerned the Home Office has used deprivation of citizenship powers as a “punishment”.

They highlighted a ruling in 2021 where Strasbourg ruled the UK failed to protect two Vietnamese children prosecuted for drug offences despite evidence they were trafficking victims.

It asks: “Was the deprivation of citizenship analogous to a criminal prosecution? Was it a “penalty” within the meaning of Article 26 of The Council of Europe Convention on Action against Trafficking in Human Beings?”

Another of the questions asks the Home Office: “For the purposes of the Article 4 complaints made in the application, was the applicant at all material times within the jurisdiction of the United Kingdom, within the meaning of Article 1 of the Convention?”

And officials have been asked: “Did the Secretary of State for the Home Department’s decision to deprive the applicant of her citizenship engage her rights under Article 4 of the Convention?

“Did the Secretary of State have a positive obligation, by virtue of Article 4 of the Convention, to consider whether the applicant had been a victim of trafficking, and whether any duties or obligations to her flowed from that fact, before deciding to deprive her of her citizenship?”

Former Immigration Minister Kevin Foster, who was in the Home Office during the legal battles, told the Daily Express: “Yet again, the ECHR is meddling in UK affairs to defend those who had no interest in the rights of others when they backed extremists.

“Shamima Begum’s case has been considered extensively by the UK courts and the decision upheld.

“Perhaps if the ECHR was as interested in the rights of those girls affected by the grooming gangs scandal, as they are in the supporters of terrorists, they might regain some of the respect they have lost from the majority of the UK public.”

Gareth Peirce, the lawyer representing Begum, said: “Strasbourg’s communication presents an unprecedented opportunity for the UK as well as for Ms Begum – to grapple with the significant considerations raised in her case and ignored, sidestepped or violated up to now by previous UK administrations.

“It is impossible to dispute that a 15-year-old British child was in 2014-15 lured, encouraged, and deceived for the purposes of sexual exploitation to leave home and travel to ISIL-controlled territory for the known purpose of being given, as a child, to an ISIL fighter to propagate children for the Islamic State.

“It is equally impossible not to acknowledge the catalogue of failures to protect a child known for weeks beforehand to be at high risk when a close friend had disappeared to Syria in an identical way and via an identical route.

“The police failed to warn families, informed the school that its apprehension of risk was overstated, conducted no safeguarding measures, delayed contact with ports and known routes of travel to trigger alarms and prevent [them] reaching the known destination.”

A Home Office spokesperson said: “The Government will always protect the UK and its citizens.

“That is why Shamima Begum — who posed a national security threat – had her British citizenship revoked and is unable to return to the UK.

“We will robustly defend any decision made to protect our national security.”