Fianna Fáil and Fine Gael have welcomed the news that Green Party TDs will join their negotiating teams in formal coalition talks.
The Greens' 12 seats would give a new government a slim majority, which is expected to be bolstered by deals with independents.
But the party says any programme for government would have to be "transformative on climate action" and approved by a two-thirds majority of its members.
Mícheál Martin says members of Fianna Fáil know the country urgently needs a government with the authority to deal with the pandemic.
Speaking this evening he says: "All of them [Fianna Fáil members] get the urgency and the necessity of this because of the crisis Covid-19 has brought on the country and the world.
"A lot of people get the necessity to deal with the existential crisis that climate change represents as well.
"Obviously there are many other members who have concerns and would be worried about it [coalition government].
"But it seems to me that the overarching consideration for the needs of the country, the people of the country, over above party self-interest."