The only trade union to reject the Haddington Road agreement on public sector pay, Unite, is to re-ballot its members, recommending a yes vote.
It comes as the Association of Higher Civil and Public Servants voted to accept the agreement this afternoon.
Unite members met this morning and discussed the acceptance by other unions of the deal.
The union said it was deciding reluctantly to recommend acceptance of the deal as its members would otherwise be disadvantaged.
The union had previously rejected the proposal to extend the Croke Park Agreement.
The Association of Higher Civil and Public Servants said that 64% of those who voted supported the proposals, while 36% voted no.
Previously the association's membership had rejected the proposal to extend the Croke Park Agreement, with 85% voting no to the extension of the agreement.
General Secretary of the association, Dave Thomas, described this agreement as a modest improvement on the provisions of Croke Park Two.