Green Party leader Trevor Sargent has said his party could not be part of any Government that included Fianna Fáil TD Frank Fahey.
Mr Sargent, who is holding a party "think-in" in Co Wicklow, said he would make up his mind on potential coalition partners after next year's election but did not totally rule out Fianna Fáil.
He said: "There is a mood for change within the Green Party, and certainly Fianna Fáil doesn't come into the equation.
"(But) if they were ruled out by us, then a vote for us would not be for the Green Party but for somebody else who we would be propping up."
He added: "I would say if you're reading the straws in the wind, it's very likely that the people, not just in the party, but in the country, want a change of government."
At the two-day event the parliamentary party debated general election strategy with candidates and fine-tune policies on climate change, at the Brooklodge Hotel, Co Wicklow.
Dáil strategy and national policies on transport, housing and energy were also featured on the two-day agenda, which concludes tonight.
The party will be fielding a record 24 candidates in constituencies around the country at the next election.
Deputy leader Mary White said the party was hopeful of making gains across the country. "I believe we can gain a few seats in rural areas that will transform the party into a truly national party," she said.
Elsewhere, Sinn Féin's five TDs will gather in Dublin tomorrow while Fine Gael, Labour and the Progressive Democrats will all convene in coming weeks before the Dáil returns on September 27th.