Ibrahim Halawa has had his trial delayed in Egypt once more.
Amnesty International, who are calling for Mr Halawa's unconditional release, said it is the fifteenth time the Dubliner's trial has been delayed.
Mr Halawa was arrested by the Egyptian army as he took refuge in a Cairo mosque while Muslim Brotherhood protesters staged a "day of refuge" outside in August 2013.
He is facing a mass trial alongside 493 other defendants, and faces a possible death sentence.
The Department of Foreign Affairs said that the hearing did not proceed today as 2 October was designated the start of Hijra (Islamic New Year) and a public holiday in recent days.
A new trial date has been set for 12 November.
The Minister for Foreign Affairs Charlie Flanagan spoke to Egypt's Ambassador to Ireland, Soha Gendi, today.
He expressed his concern about further delays and underlined the Government's strong desire to see Ibrahim returned to Ireland as a matter of urgency.
Mr Flanagan said: "I am very disappointed that the case hearing did not go ahead today.
"We are working closely with Ibrahim's family and with his lawyers in Dublin and Cairo," said Mr Flanagan.
He said Ireland's Ambassador to Egypt, Damien Cole, spoke to Ibrahim's Egyptian lawyers today.
"We are seeking urgent clarification from the Egyptian authorities in respect of the next hearing date," said Mr Flanagan.
"I want to reaffirm to Ibrahim, his family and his friends of my own and the Government's ongoing commitment to secure his return to Ireland as soon as possible and to ensure his welfare during his detention," he said.
Green Party Deputy Leader Catherine Martin expressed her disappointment at the postponement today.
"15 trial dates over 1,142 days and still no justice in sight for Ibrahim Halawa. Ibrahim, arrested when he was 17 may yet turn 21 in an Egyptian prison with no evidence ever been laid against him and no opportunity to present a defence," she said.