A government counter-radicalisation programme was considering giving the Parsons Green tube bomber the all-clear when he launched his attack injuring more than 50 people.

Ahmed Hassan’s case was discussed by a multi-agency panel set up to assess his risk of being drawn into terrorism less than a fortnight before he planted a bomb on a tube train.

A Home Office inquiry since he was jailed for 34 years in March found that no formal written plan was put in place during the 15 months that he was subject to the Channel programme.

The programme focused on his education and paid too little heed to his mental health problems and absences from his foster home, the Home Office permanent secretary, Sir Philip Rutnam, has said, in a letter to Yvette Cooper, chair of the home affairs select committee.

The final meeting of the Channel panel discussed Hassan’s case was on 5 September, Rutnam said. At this point, “considering the ongoing vulnerability assessment and intelligence update, the Channel panel was in the process of considering closure of Ahmed Hassan’s case”.

Hassan detonated the bomb 10 days later.

On receiving the letter, Cooper said it was “a matter of serious concern” that Home Office guidance on the Channel programme had not been followed in Hassan’s case.

“It is crucial that the Channel programme works effectively to deal with individuals who could pose a serious risk to public safety or national security,” she said. “We will pursue with Ministers why there were problems in this case and what further action is needed to improve the way the programme operates in future.”

His Old Bailey trial heard he had made the bomb by creating triacetone triperoxide (TATP), a powerful but unstable explosive. He made an initiator using a halogen bulb.

Around the device he had packed 2.2kg of shrapnel, including five kitchen knives, two screwdrivers, nails and screws.

Hassan denied attempted murder and causing an explosion, telling the court that he had made the bomb because he was “very bored, very depressed, very confused” and wanted to draw attention to himself.

The jury heard that both Hassan’s parents were dead by the time he was six, and he told one of his college lecturers that he believed he had “a duty to hate Britain”, which he blamed for the death of his father in an air raid on Baghdad.

He had also complained about the ongoing airstrikes against Iraq, sending a text message to the same lecturer in which he said: “Your country continues to bomb my people daily.”

Hassan made his way from Iraq to the UK in 2015 via Istanbul and Calais, and entered the country in October that year in the back of a lorry. He told police he was 16.

He was placed in the care of Surrey county council and in June he was referred to Channel. There were nine meetings to discuss Hassan during the 15 months he was subject to the scheme. Police spoke to him twice as part of the programme, in August and November 2016.

These meetings did not raise any additional concerns about Hassan’s risk of becoming involved in terrorism, although concerns were raised about his “demeanour and behaviour” by a Channel panel member in January 2017. There were no panel meetings to discuss him between January and June.

Rutnam said a series of measures were being taken to improve the working of Channel panels, and the communications between police, immigration officials and social care staff.

Mental health practitioners will in future attend all panel meetings that are considering an individual with mental health needs; panels will discuss ongoing cases every month and cases will be reassessed every three months.

Surrey county council said it was a “difficult case in tough circumstances”. A spokesperson said: “Our work with other agencies in this case wasn’t as good as it should have been and we’re sorry for our part in that.

“We knew before the terrible incident at Parsons Green that we needed to make changes and had already begun to do so.

“Since then we have made further improvements and continue to focus on ensuring our work in this area is as good as it can be. Our thoughts remain with everyone affected.”

The bomb partly detonated, sending a fireball through a packed District Line tube train. Survivors spoke of feeling their faces being simultaneously burned and cut by flying glass. Others suffered crush injuries as people fell over each other while trying to escape.