The Minister for Defence, Mr O'Dea, says he is not prepared to "abandon the triple-lock" mechanism to allow Defence Forces personnel to participate in the battle groups or so-called rapid reaction forces.
The Government last year agreed in principle with proposed Irish participation in such battle groups, but Mr O'Dea said that "there are a number of obstacles", the biggest of which was whether a UN Security Council mandate "can be obtained more quickly than at present".
The triple-lock requires a Government decision, Dáil approval and a mandate from the UN Security Council.
Fine Gael's defence spokesman, Mr Billy Timmins, said in this country "we treat the UN in the same way as a dysfunctional family uses a comfort blanket, and the time has come to make decisions for ourselves on a case-by-case basis".