The family of Irishman Ibrahim Halawa who has spent the last four years in jail in Egypt are preparing to sue over delayed verdicts in the trial.
Ibrahim Halawa, 21, had been expecting a judgement on Monday on charges over Muslim Brotherhood protests which took place in Cairo in August 2013.
Following the latest delay, Egyptian president Abdel Fattah el-Sisi reiterated his position to the Taoiseach Leo Varadkar that he could not intervene until verdicts were delivered.
Somaia Halawa, one of Ibrahim's sisters, questioned the judge's decision not to give verdicts.
"You just feel that there is something that's in this trial that no-one knows," she said.
Ibrahim Halawa, a student and son of a prominent Muslim cleric in Dublin - Sheikh Hussein Halawa - was jailed after being detained in a mosque near Ramses Square in Cairo four years ago amid protests over the removal of president Mohamed Morsi. He was 17 at the time.
Along with scores of others he is accused of murders, bombing, possession of firearms and explosives, arson, violence against police and desecration of Al Fatah Mosque.
No specific evidence was introduced in the long-running trial relating to the Dubliner.
It is understood no formal explanation was given for the delay in the verdicts but there were unconfirmed reports of references to security concerns and a threatened prison escape by inmates involved in another case.
Mr Halawa's solicitor Darragh Mackin, of Belfast-based human rights legal firm KRW Law, has spent a year preparing a legal case against Egypt over the delays in the mass trial.
The ending of the trial would clear the way for president el-Sisi to use Decree 140 to deport Mr Halawa, a commitment he gave a delegation of Irish politicians when they visited Cairo in January.
A lawsuit is expected to be launched if the judge does not deliver verdicts on September 18.
Ms Halawa said: "Ibrahim's mental health is being played around with. We as a family can't accept it anymore.
"There has to be a deadline to this joke.
"The Egyptian government are playing with us because they know very well that there's not much pressure being put on them. They know very well we are waiting for a trial. There's no pressure to tell them you have a limit."
Mr Halawa is said to have become more withdrawn since the latest delay.
His older brother, Ahmed, visited him in Wadi Natrun prison.
"He just feels hopeless," their sister Somaia said. "He doesn't want to talk. He just feels that he has lost trust in everything, even his own brothers and sisters.".
Mr Halawa is facing the threat of a death sentence if found guilty.
Hearings in the mass trial involving Mr Halawa and 493 others have been adjourned and delayed numerous times over the past four years. The prosecution case ended last month.