Tánaiste Eamon Gilmore has said he is becoming increasingly concerned about the detention of the Halawa family in Egypt following an army crackdown on the Muslim Brotherhood.
The four family members, who are Irish citizens, have been detained without specific charge since August.
The family’s detention was extended for a further 45 days on 30 September.
Speaking on his arrival at a meeting of EU foreign ministers in Luxembourg, Mr Gilmore said: "I remain very concerned about the continuing violence in Egypt and also the detention without trial of some of the people who were involved in the protest activity."
He said he would be raising the case of the Halawa family with his counterparts and said the use of detention without trial was not the "appropriate" response.
Mr Gilmore said: "Dealing with terrorism is always difficult for any government, but any government, any set of authorities have to act proportionately.
"I think that the use of violent methods, the use of detention without trial, without bringing charges against people who have been detained, I think that that is not the appropriate way.
"We have four Irish citizens who have been detained since August, no charges have been brought against them."
EU foreign ministers are also discussing the latest developments in Syria, including progress on removing the Assad regime's chemical weapons.
They are also meeting the Burmese pro-democracy campaigner and Nobel Peace Prize winner Aung San Suu Kyi.
Mr Gilmore said the Government would be coming forward shortly with an aid package for Burma, which is also known as Myanmar.