Tanaiste Eamon Gilmore has urged the Egyptian authorities to show restraint following its crackdown on supporters of the ousted president that left more than 500 people dead.
The foreign affairs minister condemned the heavy use of force to clear protests in Cairo yesterday.
A month-long state of emergency was declared by the interim government in Cairo following the violence, sparked by the police raid to oust supporters of ex-president Mohammed Morsi.
"I call on the authorities to show the utmost restraint at this point, and on all sides in Egypt to refrain from further violence, and to work to overcome their differences in the interests of their country and people," Mr Gilmore said.
He said it was "deeply regrettable" that the restraint shown until now by the authorities was abandoned yesterday.
"In addition to the many people killed or injured, it is also deeply worrying that these events may further polarise society, make an inclusive political dialogue even more difficult, and lead to a continuing spiral of violence," Mr Gilmore said.
The official death toll in the clashes - which have drawn worldwide condemnation for the government's actions - has risen to more than 500.
Leaders of Mr Morsi's Muslim Brotherhood claim far more were killed in what they describe as a "massacre" on the streets of the capital.
The streets of Cairo were reported to be uncharacteristically quiet in the wake of the deadliest day of violence in the country since the 2011 pro-democracy uprising.
Sky News cameraman Mick Deane was among three journalists killed.
A march has been called by the Muslim Brotherhood, which said it remained committed to non-violent action to reverse the military coup which removed Mr Morsi, the country's first freely elected leader.
He was ousted in June amid mass protests against his year-old regime, which critics said had failed to address key economic and political issues and gave undue influence to the Brotherhood.
Mr Morsi and other leaders from the movement have been arrested.
In a blow to the new administration, Nobel Peace Prize-winner Mohamed ElBaradei resigned as Egypt's interim vice president in protest at the repression.
"I cannot take responsibility before God, my conscience and country for a single drop of blood, especially because I know it was possible to spare it," he said.
Meanwhile, the Tanaiste said he is being kept informed of continuing developments.
He said the Irish Embassy in Cairo remains open, but its opening hours may be restricted if the security situation worsens.
"Irish citizens are advised to avoid non-essential travel to Egypt at the present time, with the exception of the Red Sea resorts," Mr Gilmore added.
"Irish citizens in Egypt and those intending to travel, are advised to register on my department's website, monitor the situation closely and check the department's travel advice on a regular basis for any updated information."