Mary Lou McDonald will be proposed for Taoiseach when the Dáil resumes later this week, but the Sinn Féin leader is unlikely to be elected as no government has yet been formed following the general election earlier in February.

Other party leaders are also likely to be proposed as taoiseach, including Fine Gael’s outgoing Taoiseach Leo Varadkar, although he has already indicated he is prepared to go into opposition and that Sinn Féin and Fianna Fáil should form a coalition.

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McDonald, whose party topped first preference voting in the election, has said she is prepared to go into power and she could still lead a minority left-leaning government, despite the numbers making it difficult.

It could be the end of March before a working coalition is formed and many observers feel, with Fine Gael ready to go into opposition instead of forming a grand coalition with Fianna Fáil, a deal might yet be agreed between Sinn Féin, Fianna Fáil, and the Greens or smaller parties and a group of independents.

Fine Gael leaders Leo Varadkar and Simon Coveney.

Fine Gael leaders Leo Varadkar and Simon Coveney.

Sinn Féin won the popular vote on February 8 but its 37 seats are not enough to unlock the 160-seat Dáil, even with the support of smaller left-wing parties.

McDonald said on Monday, “There is undoubtedly a solid block of TDs for change for a new government.  I remain very determined that we deliver that government.”

She added, “We have been elected in very large numbers to be in government, even to lead the next government. I’ve also said that the idea of seeing Fine Gael or Fianna Fáil returned again for five years is unthinkable.”   

Fine Gael TDs declared their plans to enter opposition after a six-hour meeting on Monday. The party said in a statement that Varadkar “relishes the challenge” of leading a “strong and effective” opposition.

Varadkar will remain as caretaker taoiseach if no replacement can command a majority in the Dail this week.  The statement said that Fine Gael will not enter talks on a program for government without a mandate from its TDs.

It added, “Sinn Féin has an obligation to the people who voted for it to show whether or not it can honor the extraordinary promises they made. If Sinn Féin fails in that challenge then the onus passes to Fianna Fail to form a government with them, or with the Greens, Labour and Social Democrats.”     

After Monday’s Fine Gael meeting Varadkar said Sinn Féin and Fianna Fáil should try to form a government with each other and that Fine Gael is prepared to go into opposition.

He did not rule out Fine Gael entering government with Fianna Fáil as a last resort, but added, “I don’t foresee that happening. The future is about leading the party into opposition.”

Negotiations between the parties and independents still have a long way to go, with much still depending on decisions in Fianna Fáil which retained 38 of its 44 seats, Sinn Féin which increased its seats from 23 to a poll-topping 37 with only 42 candidates, and Fine Gael which retained 35 of its 47 seats.

Remaining seats went to independents 21, Green Party 12, Labour 6; Social Democrats six and Solidarity-People Before Profit five.

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