The Government has a responsibility to lobby "very hard for due process" to secure the release of Ibrahim Halawa from prison in Egypt, an Australian journalist has said.
Peter Greste was detained alongside Halawa after being arrested in Cairo in 2013 for reporting news that the authorities said was "damaging to national security".
The Al-Jazeera journalist said it seemed wrong to him that Mr Halawa was not getting the same level of support that he did.
Mr Greste made the comments in an interview which will be broadcast on RTÉ Radio 1's Documentary on One programme on Saturday.
Irish citizen Ibrahim Halawa was arrested with his three sisters in Egypt in August 2013, following a protest at the Al-Fateh mosque in Cairo. He was 17 at the time of the arrest.
He has remained in Egyptian custody since and is charged with terror offences alongside 493 others in a group trial. His sisters have since been released.
His trial has been postponed 13 times and is now due back in court on June 26th.
In the radio documentary, entitled Cairo Cellmates, Greste discussed his imprisonment in Cairo's Tora Prison alongside Mr Halawa.
He said his own case came to symbolise an international fight for democratic principles and basic human rights, and that Mr Halawa’s case is symbolic for the same reasons.
“Narratives are really important and sometimes the way something is presented will influence the way people see things, when fundamentally there is no difference between people’s stories,” he said.
“We got support because my name was Peter, not Ibrahim, and we got support because I’d a family who were articulate and comfortable in front of cameras.
“We got the support of lots of friends in media who understood that I wasn’t involved and were outraged at what happened to us.”
Dual identity
He said he feels a kinship with Mr Halawa, who he believed was a victim of his dual Irish-Egyptian identity.
“Conversations about his relationship with Egypt, his supposed politics and what he was up to - all those issues need to be put to one side.
“They are irrelevant to the central issue that Ibrahim Halawa has been denied due process, even by Egyptian standards.
“He has been detained far longer than legally allowed, been denied the opportunity to defend himself in court and there is no evidence.
“It is incumbent on the Irish Government to defend and argue those points - what he believes in is beside the point.”
He said the Government and the EU needed to argue forcefully for Mr Halawa’s rights as an Irish man and a European citizen.
Speaking separately in an interview on RTÉ’s News at One on Friday, Greste said there was “very little doubt” in his mind that torture and abuse takes place in the prison.
He said he had every reason to believe a recent letter from Mr Halawa was truthful and that he had been experiencing “some pretty rough treatment”.
Minister for Foreign Affairs Charlie Flanagan said this week he would engage in "high-level contacts" over the coming weeks on the case.