Fine Gael is attempting to reverse the Fianna Fáil-Labour deal under which the Taoiseach has to attend the Dáil on just two of the three sitting days every week.
The move was welcomed by Labour yesterday, although it faces making an embarrassing U-turn if it supports Fine Gael when the issue is forced to a Dáil vote in the autumn.
The Dáil adjourns for the summer recess next Thursday. A Labour spokesman recalled yesterday that the party leader, Mr Pat Rabbitte, had already indicated that he would undo the decision if he could.
"We think there are some technical problems with Fine Gael's proposal, but we would support it in a Dáil vote," he added.
The Government, with its in-built majority, would win a vote on the issue. However, it would cause some embarrassment to Mr Ahern, given that all previous Taoisigh took the Order of Business on all sitting days, unless absent on official business.
The Government Chief Whip, Ms Mary Hanafin, said yesterday that the Government would oppose the Fine Gael move. "The Taoiseach spends more time in the Dáil than previous Taoisigh and his European counterparts," she added.
The deal that the Taoiseach would only attend the Dáil two days a week, and not attend the Order of Business on Thursdays, was struck between Fianna Fáil and Labour last year, shortly before Mr Rabbitte became Labour Party leader.
The deal was agreed in return for the reinstatement of Labour as a party taking precedence over the technical group under Dáil procedures.
The technical group is made up of Sinn Féin, the Green Party and a number of Independents.
The Order of Business on Thursdays is now taken by the Tánaiste, Ms Harney, or the Minister for Defence, Mr Smith.
A Fine Gael Private Member's motion reversing the standing order, giving effect to the agreement, is to be included in the Dáil's Order Paper next week.
Party sources said that the motion would be moved in the autumn if the Taoiseach continued to refuse to take the Order of Business on Thursdays.
The Fine Gael spokesman on agriculture, Mr Billy Timmins, a trenchant critic of the FF-Labour deal, said yesterday he hoped Mr Ahern would reflect on the matter during the summer.
"The Government has 80 press advisers," he said. "The only opportunity the Opposition has to expose the Government is in the Dáil, and the Taoiseach should be present on all sitting days to answer questions."
