Fine Gael, Fianna Fail and the Green Party have voted to go into government, marking the beginning of a historic coalition.
Ireland’s next Government will be formed on Saturday after the parties voted resoundingly to enter coalition.
Members of the environmentalist party decided by a 76% majority to form an administration with the rival parties.
Fine Gael members backed the programme for government with some 80% voting in favour while 20% of members voted against.
Fianna Fail members also endorsed the historic blueprint, with 74% backing the agreement.
The three parties signed up to a programme which promises radical action on climate change but will also have to shoulder the burden of leading the country’s economic recovery from Covid-19.
Speaking after the result, Green Party leader Eamon Ryan said: “There’s a sense of responsibility on us now because we do have a job to do.
“We have to go in and help work with our coalition partners in Government in actually getting our country out of a really severe economic crisis.
“People at home who are losing their jobs or maybe at risk of that, they want a government to get up and stand up for them and get everyone back working.
“We commit to doing that to tell you everything we can, there’s work to be done, and we’re the ones to try and help make it happen.”
Mr Ryan added: “I believe we can work with our coalition parties and the parties in opposition in the Dail, to work together collectively to set our country on this new future.
“One that is sustainable in every way: socially, economically and environmentally.
“That’s what we will seek to do.”
Fianna Fail leader Micheal Martin will take over the role of Irish premier in a historic reconciliation of a political feud with Fine Gael dating back to the foundation of the state a century ago.
The two larger parties needed the support of the Greens to have a working majority in the Irish parliament, equating to around 80 seats.
February’s election was inconclusive and efforts to strike an agreement were hampered as the country’s caretaker Government coped with the pandemic.
There will be a full sitting of the Irish parliament – the Dail – in the Convention Centre, Dublin, on Saturday morning to elect Mr Martin as the new Taoiseach.
The Dail cannot sit in Leinster House as usual due to social distancing as every TD needs to be there to vote.
As part of a pact between Mr Martin and Mr Varadkar, Mr Martin will take the role of Taoiseach until December 2022 with Mr Varadkar resuming the Taoiseach role for the remainder of the Government term of office.
Mr Martin said that while his party voted in favour of going into coalition, there are “many challenges” ahead.
“I do not understate the gravity of the situation facing the country, but on the other hand, it’s also a moment of opportunity and a moment of hope for our people that we face up to the challenges, overcome them and lead to a better type of society,” he said.
“(A society) where people can have access to homes, where people can have access to a good quality health service, and where we can meet the existential challenge of our time, namely climate change, in a far more energetic and effective way than we have in the past.”
Mr Varadkar said he was looking forward to helping people get back to work and businesses open again following the pandemic emergency.
He added: “Fine Gael is going to enter a third term in government and this new coalition, united and strong and up for the challenge.
“(I’m) looking forward to helping the country get through the Covid emergency.”
Catherine Martin, deputy leader of the Green Party, said acknowledged that some members are “disappointed” by the outcome.
“I want to assure all members who did not support this programme for government that we have heard you and we value your concerns,” she said.
“Your vigilance and oversight is more vital now than ever before.
“You can be assured that we will work every day to ensure that this Government will deliver for all the people of Ireland.
“The Green Party is stepping up to serve its country, putting people before politics.
“It won’t be easy, but we intend hitting the ground running, entering government in good faith, realising that there is a job of work to be done and to serve the people to the very best of our ability.
“We must build up trust all around with our very soon-to-be new coalition partners.”
Prime Minister Boris Johnson congratulated Mr Martin on his impending role.
Mr Johnson tweeted: “Ireland is our closest neighbour, good friend and ally on issues such as climate change, the global fight against Covid-19 and our shared values on human rights and democracy.”