A verdict is expected today in the trial of Irish citizen Ibrahim Halawa.
The 21-year-old has been held in a Cairo jail since 2013.
He was arrested along with hundreds of other individuals during peaceful protests against the ousting of former president Mohamed Morsi.
The trial process has been beset by more than 30 adjournments but a verdict is finally expected today.
Taoiseach Leo Varadkar spoke by phone with Egyptian President Abdel Fattah Al-Sisi when the last trial was adjourned three weeks ago.
During the 25-minute phone call, the Taoiseach expressed his disappointment.
He made clear to Mr Al-Sisi that his priority was to secure the return of Mr Halawa to Ireland as soon as possible.
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 Irishman.
Mr Halawa is facing the threat of a death sentence if found guilty.
The Irish citizen imprisoned in Egypt while awaiting trial for the past three years has written a poignant letter describing his experiences in jail.