A cross-party group of TDs has met Ibrahim Halawa in prison in Egypt.
Speaking to RTÉ News from Egypt, Mr Ó Fearghaíl said Mr Halawa "looked healthy and was in very good spirits despite being deeply frustrated" by his situation.
He said the 21-year-old made repeated requests to be allowed to return home.
Mr Halawa told the TDs about a hunger strike that he has been on intermittently and all representatives asked him to refrain from the strike and to look after his health.
Tomorrow, the delegation of TDs will meet with the Egyptian president and the speaker of the parliament.
As well as raising bilateral issues between Ireland and Egypt, the representatives will highlight Mr Halawa's situation.
Mr Halawa, who is from Firhouse in Dublin was arrested at a protest in Cairo in 2013 and his trial has been postponed 17 times.
The son of Ireland's most senior Muslim cleric, he was arrested in a mosque during disturbances in Cairo in August 2013 and has been imprisoned ever since.