DUBLIN, Ireland — Ireland’s Parliament appointed Micheal Martin, a center-right politician, as prime minister on Saturday as the country deals with the headwinds of the coronavirus and fallout from a housing crisis.
Mr. Martin replaces Leo Varadkar, a doctor who drew acclaim for his handling of the coronavirus outbreak but who had been a caretaker prime minister since a February general election delivered a loss of seats for his party but no clear winner.
The new government, the result of more than four months of negotiations, will be the first to include the country’s two rival center-right political movements — Fianna Fail, led by Mr. Martin, and Fine Gael, led by Mr. Varadkar. The two parties have alternated in power since the foundation of the modern Irish state in 1922.
Together with the smaller Green Party, the rivals must now try to steer Ireland through what is likely to be a period of turbulence, with neighboring Britain’s departure from Europe’s single market contributing to economic and political uncertainty.
The path to a new government was cleared on Friday evening when Green Party members voted decisively to support joining the coalition after extracting concessions on environmental initiatives. The concessions included lowering Ireland’s carbon emissions 7 percent annually through 2030, an increase in the carbon tax, and an emphasis on public transit and cycling and pedestrian infrastructure.
The decision quashed fears that younger, more left-wing party members would reject an alliance with the center-right.
While the coalition’s program promises to address crises in housing and health care, critics on the left of the Green Party said it did not commit the government to allocating enough funds for major changes.
The agreement to form the new government comes after a turbulent period in Irish politics, in which Mr. Varadkar’s government was toppled amid voter anger over a housing crisis, rising rents and a failing public health service.
Those frustrations lifted the fortunes of the center-left Sinn Fein party, which was formerly the political wing of the Irish Republican Army before it committed itself to democratic, nonviolent means.
The emergence of Sinn Fein’s leader, Mary Lou McDonald, as head of the opposition — potentially allied with several smaller left and center-left parties — could help propel a long-term realignment of Irish politics along a more conventional left-right divide.
In the meantime, the coalition will govern under a power-sharing arrangement in which Mr. Martin will stand down in two years to be replaced either by Mr. Varadkar or by whoever is then leader of Fine Gael.
A 31-year veteran of the Irish Parliament, Mr. Martin, 59, took over the leadership of Fianna Fail in 2011 shortly before it suffered a stinging election defeat, losing 51 of its 71 seats amid anger over its handling of a disastrous property bubble. The meltdown forced Ireland to accept a 67.5 billion euro ($95 billion) bailout organized by the International Monetary Fund.
Despite having a conservative reputation, Mr. Martin has since supported the holding of referendums on same-sex marriage and abortion, aligning with an increasingly liberal mood in Ireland. These policies clashed with many of his party’s predominantly rural and conservative members of Parliament and its supporters.
As health minister in a previous Fianna Fail-led government, Mr. Martin introduced the world’s first nationwide ban on smoking in all workplaces, including Ireland’s famously smoky pubs. Initially greeted with skepticism and strong resistance, the 2004 smoking ban proved both successful and ultimately popular, and similar approaches have since been adopted in many other Western countries.
Accepting the nomination as prime minister, he said that to be elected as political leader of a free republic was the greatest honor anyone could receive.
The most difficult job facing the new government will be its response to the pandemic, said Mr. Martin, who also paid tribute to Ireland’s health care workers.
“Our country has shown time and time again that we can overcome the toughest of challenges,” he said, “and we will do so again.”