A convicted terrorist accused of grooming Manchester Arena bomber Salman Abedi will not answer any questions if he is forced to attend the public inquiry into the atrocity, a court has heard.

The bereaved families of the 22 people killed in the explosion want Abdalraouf Abdallah, 28, to explain his links to Abedi and explore how the suicide attacker became radicalised.

The inquiry’s legal team served a notice on him this summer to attend the hearing in Manchester next Wednesday, but Abdallah’s lawyers argue that would infringe his human rights and violate his privilege against self-incrimination.

On Thursday, counsel to the inquiry Paul Greaney QC said: “Mr Abdallah has evidence of a high degree of potential relevance to give in relation to issues in relation to the radicalisation of Salman Abedi, and the planning and preparation for the Arena attack.

“As is publicly known, he is currently serving a sentence for terrorism offences and he was in contact with Salman Abedi both in person and electronically from 2014.

“Moreover he is regarded by the inquiry’s instructed expert on radicalisation, Dr Matthew Wilkinson, as responsible for, as he puts it, grooming Salman Abedi into the violent Islamist extremist worldview.”

In July 2016 Abdallah, from Moss Side, Manchester, was given a extended sentence of nine and half years, with a custodial term of five and a half years, after he was convicted of preparing and funding acts of terrorism by helping four others travel to Syria.

Abedi, 22, twice visited Abdallah in prison and was in contact via a mobile phone smuggled into jail in the months leading up to the Arena bombing on May 22 2017.

The inquiry has heard Abdallah was diagnosed with post-traumatic stress disorder after he became a paraplegic when injured in fighting in Libya in 2011 during the country’s uprising.

His barrister, Rajiv Menon QC, said that up to May 2020, when his client was first contacted by the inquiry, his medical records showed three incidents of self-harm in prison, but since then it had “markedly increased”, with 12 more self-harm incidents recorded, including, he said, an attempted suicide.

He submitted: “We say the evidence is clear, there is a real and objectively well-founded risk that Abdalrouf Abdallah will seriously and imminently self harm again if compelled to give evidence to the inquiry.”

Consultant forensic psychiatrist Dr John Kent, instructed by the inquiry to interview Abdallah last month, said his motivation for self-harm was varied and some had been linked to frustrations with the prison regime, including vaping on one occasion.

The doctor told Mr Greaney it was “very difficult” to assess whether the recent incidents could be manipulation by Abdallah, designed to avoid giving evidence.

A psychiatrist instructed by Abdallah’s legal team has said he is unfit to give evidence and making him do so could risk self-harm and suicide.

Addressing the issue of self-incrimination, Mr Menon said: “Forcing him to attend either in person or via CVP (videolink) and subjecting him to hours of questions that he will not be answering is, with all due respect, a pointless exercise and will serve no purpose other than to dehumanise and humiliate an already vulnerable man and frustrate all those who want him to answer questions.

“If there is a real and an appreciable risk that an answer that Mr Abdallah were to give may be used against him in criminal proceedings, he is entitled to refuse to answer that question.”

He said that counter-terrorism police had previously interviewed his client under caution as a suspect in the Arena attack and the following year, last summer, he was asked “similar if not identical questions” in prison by inquiry officials.

Mr Menon said: “In those circumstances he felt, and we say justifiably so, that he was being treated as a suspect both by the police and the inquiry.”

He said Dr Wilkinson’s expert report which concluded Abdallah groomed Abedi and was “effectively a co-conspirator” in the Arena attack was a “preposterous suggestion speculated at best without any proper evidential foundation”.

The inquiry also heard Abdallah told Dr Kent in one of his two interviews that he did intend to give evidence at his forthcoming parole board hearing, although Mr Menon said no date had been set for it yet and he had not given any legal advice to him over the matter.

Abdallah, who denies grooming Abedi or any involvement in the Arena attack, was released from jail in November on licence before being recalled in January – reportedly over a breach of a general condition requiring good behaviour.

Inquiry chairman Sir John Saunders said he will make a ruling “as soon as possible” on whether Abdallah should be compelled to attend next week, either in person or by prison videolink.

The inquiry was adjourned until next Tuesday.