The Government will have the support of the two Green Party TDs in Dail votes designed to end TDs' and senators' rights to sit on local authorities.
The decision to support the Local Government Bill was taken during a meeting yesterday in Dublin of all Green elected representatives. "The banning of the dual mandate has always been a core Green Party principle," said Mr John Gormley TD.
However, the Greens would push for changes to the legislation: "For instance, having directly elected Lord Mayors, while a welcome move, means nothing if the person selected has no real executive power."
Many senior Fine Gael figures support ending the dual mandate, though the plan is strongly opposed by the four Independent TDs allied to the Government, Mr Jackie Healy-Rae, Ms Mildred Fox, Mr Harry Blaney and Mr Tom Gildea.
However, Fine Gael is unlikely to make it easy for the Government when it comes to a Dail vote.
The Greens' decision "puts it up" to the Taoiseach, said Mr Gormley. The guarantee of their vote will put Mr Ahern into "something of a quandary". "Does he now decide to temporarily dispense with his four Independent allies and put through this Bill with the help of the Greens, thus jeopardising the long-term future of this Government, or does he cave in to their small-minded approach to politics and once again hang his hapless Environment Minister out to dry?
"It would have been very convenient for the Taoiseach to allow things to take their normal course. Then he could have shrugged his shoulders and told Minister Dempsey that he had no real choice.
"The Green Party decision is going to force him to make a choice."