Campaigners have backed calls for a medical specialist to be allowed to visit a Palestinian inmate currently being held in Maghaberry Prison.
Dr Issam Hijjawi Bassalat is one of 10 people charged in relation to an MI5 operation targeting the 'IRA' - sometimes referred to as the New IRA - earlier this year.
He denies any wrong doing.
Campaigners say Dr Bassalat suffers from several health problems including a neurological issue resulting from a disk prolapse, which causes severe pain.
Scotland Against Criminalising Communities recently wrote to justice minister Naomi Long and Secretary of State Brandon Lewis asking that a neurologist be brought into the Co Antrim prison to treat Dr Bassalat.
Last month Dr Bassalat and republican prisoners across Ireland launched a hunger strike after he was placed in coronavirus isolation in the prison's Foyle House following a hospital visit.
The protest was called off after he was transferred to a wing at the prison used to house republican prisoners.
They say he is again due to attend another medical appointment outside the prison which will result in him being isolated for a further 14 days on his return.
“We believe that it is imperative that Dr Bassalat receives specialist medical attention, and that isolation in Foyle House presents an unacceptable and unnecessary risk to his health,” the letter said.
A spokesman for the Prison Service said: “ The Northern Ireland Prison Service can confirm it has received correspondence and will respond in due course.
"While the Prison Service does not comment on individuals in our care, we work in partnership with the South Eastern Health and Social Care Trust to ensure all prisoners receive the appropriate health care.”
