The Green Party will not participate in a Rainbow coalition after the next general election unless changes are made to the Nice Treaty on European integration.
The party leader, Mr Trevor Sargent, told The Irish Times last night that his party's involvement in a future coalition with Fine Gael and Labour would depend on a protocol being attached to the treaty to protect Irish military neutrality.
"The other parties will be tip-toeing around this, but in our case the Nice Referendum is dead," Mr Sargent said. "It is not acceptable to us to run the same poll twice. There would have to be a protocol attached, dealing at least with neutrality, that would have to be clarified."
The Nice Treaty has to be passed by referendum by next December if EU enlargement is to go ahead.
The pre-election skirmishes between the political parties continued yesterday. The Fine Gael leader, Mr Michael Noonan, described the race as being "well and truly on".
Asked about a pre-electoral pact with Labour, Mr Noonan said that Fine Gael's preference would be for the voters to be "provided with a clear alternative government" in advance of the election. He added: "However, it is a matter for Labour to decide its own position."
The Fine Gael leader said there was an emerging view among voters that it was time to get rid of Fianna Fáil. "We are the only party which is stating clearly that we will not put Fianna Fáil back into power under any circumstances."
Later, speaking on the Last Word programme on Today FM, he said he believed Fine Gael and Labour could gain seven seats in the election, giving them an overall majority. "But I totally respect, from a tactical point of view, that they (Labour) have to fight the election as they see fit."
On Sunday, the Taoiseach, Mr Ahern, said his preference would be to return to government with the Progressive Democrats. However, the junior coalition party has already ruled out a voting pact. The Taoiseach also kept his options open in relation to Labour and underlined his record on social partnership.
However, following the Taoiseach's remarks, the Labour leader, Mr Ruairí Quinn, was critical of the Government's performance, saying that Mr Ahern had made a number of claims about his Government's achievements which were "patently false".
The former Labour leader, Mr Dick Spring, said yesterday that he would like to be appointed a cabinet minister after the general election and would serve in a coalition with Fianna Fáil.
Mr Spring said his preference, and that of his party, would be to form a Rainbow coalition with Fine Gael and possibly the Green Party. However, if that was not possible, "one would have to look around to see what is available to make a government".
Mr Sargent said that he had had preliminary discussions on a possible future coalition with both Mr Noonan and Mr Quinn, but the talks had not been detailed in nature.
He said that the Greens would not become involved in any pre-election pact because they did not wish to be perceived as the "tail-end of some expedient government".
"Getting what we want is not something that will necessarily happen by us saying anything before the election. We will see how strong our hand is," he added.
A Green Party conference is planned for next March and Mr Sargent said that there might be some indication then of the party's demands. "The motions put then will be the nearest things to any announcement as to how the party might go in the run-up to the election. But we may also choose not to give any indication at that time, because there may not be consensus."
Sources within Fine Gael and Labour believe that the Green Party, which currently has two TDs, may be needed to form a majority in a possible Rainbow government.
At present, Fianna Fail has 74 deputies, Fine Gael 54, Labour 21, the PDs 4 and Sinn Féin 1. There are 11 Independent deputies in the Dáil.