The British media reported on Monday that the MI5 had tried to recruit the suspected Daesh (ISIL) terrorist dubbed the 'new Jihadi John' before he fled Britain for Syria.
The Sunday Times has reported that intelligence officers gave Siddhartha Dhar the chance to work as a double agent in September shortly before he was arrested.
He travelled to the Middle East via Paris just hours after being granted police bail, added the report.
The Sunday Times reports M15 officials warned the former bouncy castle salesman he was likely to end up in jail or dead unless he worked with the security service, said The Mirror.
"M15 had a lot of intelligence on Dhar… Although he was a potential threat, he was a potential asset to MI5," reports have quoted an informed source as telling the paper.
Dhar is believed to have been the man with a British accent shown in an ISIL propaganda video released last week.
The footage showed five Syrian men being shot dead over allegations they were working as spies.
Before the execution, the man said: "This is a message to David Cameron."
Cameron, himself, described the video as a "desperate” propaganda tool used by an organisation that is losing ground.
"It's desperate stuff from an organisation that really does do the most utterly despicable and ghastly acts and people can see that again today," the prime minister told reporters.
The Jihadi John was another British member of the terrorist group who is believed to have been killed in an air strike late last year.
British officials say up to 800 Britons have traveled to Iraq and Syria, some to join ISIL. Around half of them have returned home and about 70 are believed to have been killed in the countries.