More than 40 foreign terrorists have used human rights laws to remain in the UK, according to an unpublished report delayed by the Home Office.

The study highlights the near insurmountable problem for the Government in deporting dangerous jihadists and follows a series of Islamic State-inspired attacks in the UK.

In the court cases, lawyers - typically funded through legal aid - have successfully prevented foreign-born terror suspects from being sent back to their home countries.

At a time when Britain’s security services are fully stretched, the additional burden of monitoring so many foreign terrorist inevitably adds to the strain.

Details are contained in a report ordered by Theresa May when Home Secretary into a scheme called Deportation with Assurances (DWA).

View photos Abu Qatada in 2012 Credit: AFP More

The scheme - in theory - allows the UK to expel terror suspects with guarantees they will not be mistreated or even tortured in their home country.

But it appears to have broken down allowing terrorists to remain in the UK.

The report is potentially embarrassing for the prime minister because it is expected to highlight the collapse of an initiative she pushed hard for while in the Home Office.

The DWA scheme led to the removal of Abu Qatada, a notorious al-Qaeda-linked cleric who was sent back to Jordan in 2013 to stand trial on terrorist offences. Qatada was cleared but since his case, it is understood, that no other foreign terror suspects have been returned under the scheme.

The analysis of the Government’s practice of deportations with assurances was carried out by David Anderson QC, the then independent reviewer of terrorism legislation, and co-written with Professor Clive Walker, an international law expert.

It was delivered to the Home Office in February.

Prof Walker said: “My research suggests there are more than 40 foreign terrorists convicted in the UK who have avoided deportation using the human rights act. The figure is much larger than was previously thought.”

Among those understood to have used the Human Rights Act to resist deportation including jihadists with links to the failed 21/7 bomb plot in 2005 who were jailed in the UK and subsequently released after serving their sentences.

Another is an Algerian terrorist imprisoned for funding al-Qaeda training camps but since free after serving his sentence.

View photos Osama Bin Laden supporter Baghdad Meziane Credit: Raymonds More

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