The acting Taoiseach Leo Varadkar has told a meeting of the Fine Gael parliamentary party that he "relishes the challenge" to lead the Opposition.
The party met for six hours today to discuss their next steps amid government formation talks.
In a statement from Fine Gael following the meeting, it said: "We are preparing to fo into Opposition".
It said the delegates "agreed that the onus is on Sinn Féin to form a government of the left with the support of independents".
It said: "Sinn Féin has an obligation to the people who voted for it to show whether or not it can honour the extraordinary promises they made.
"If Sinn Féin fails in that challenge then the onus passes to Fianna Fáil to form a government with them, and or with the Greens, Labour and Social Democrat parties and independents."
Leo Varadkar says the party is preparing for opposition and it’s up to Sinn Fein and Fianna Fáil to try and form a government pic.twitter.com/JUnTWQ4UrP
— Seán Defoe (@SeanDefoe) February 17, 2020
Fine Gael will "hold the new government to account" in representing the interests of people who voted for the party in the general election, it said.
Speaking to the media following the marathon meeting, Mr Varadkar conceded he won't be the Taoiseach when the next Dáil is formed.
However, while not ruling out Fine Gael being involved in government as a last resort, he said he hopes things won't come to that.
He said: "We're a long, long way from that; the election has happened and the results are clear and the onus falls on Sinn Féin to form a government with parties on the left and the independents.
"We spent on 76 days in 2016 trying to form a government and I think the onus now falls on other parties to do that and not on us.
The Taoiseach said he also plans to "consult with public representatives and members about the future direction of Fine Gael".
Mr Varadkar will engage with the other parties to discuss the outcome of the election but Fine Gael said no further negotiations on forming a government will be done without the input of the parliamentary party.
The parliamentary party will meet again next week.