Leo Varadkar, Ireland’s barrier-breaking leader, said on Wednesday that he would resign, days after a double referendum in which voters rejected constitutional changes his government had championed, and after years of waning public support for his political party, Fine Gael.
Mr. Varadkar, the son of an Irish nurse and a doctor who was born in Mumbai, became the country’s youngest-ever leader when he first took up the post in 2017 at the age of 38. He was also the country’s first gay taoiseach, or Irish prime minister, and the first person of South Asian heritage to hold the position. In many ways, he personified the rapidly changing identity of the modern Irish state.
But Fine Gael, which is ruling in coalition with two other parties, has struggled in recent years, and, before local and European elections in June, polls suggest public support for the party has flatlined.
“I know this will come as a surprise to many people and a disappointment to some, but I hope you will understand my decision,” Mr. Varadkar told said at a news conference outside Leinster House in central Dublin. “I know that others will — how shall I put it? — cope with the news just fine,” he said. “That is the great thing about living in a democracy.”
Citing reasons both “personal and political,” Mr. Varadkar, 45, said he would step down from the party leadership effective immediately and would continue to serve as prime minister until Fine Gael elects a new leader before the Easter break. That post is expected to be in filled when the government returns on April 16.
Mr. Varadkar made the unexpected announcement shortly after a cabinet meeting on Wednesday morning, his voice at times cracking with emotion.
There had been no indication of his decision just days earlier when he visited the White House and met with President Biden for St. Patrick’s Day. But Mr. Varadkar has been unable to revive the fortunes of Fine Gael since it came third in the 2020 election, when the most votes went to Sinn Fein — the party that has historically called for uniting Northern Ireland, which remains part of the United Kingdom, with the Republic of Ireland. That result was damaging to the longstanding dominance of Fine Gael and Fianna Fáil, which went on to form a coalition government alongside the Green Party.
Eoin O’Malley, an associate professor in political science at Dublin City University, said that while Mr. Varadkar’s announcement was surprising, the party had not been in a strong position politically for some time.
“This is a politician who is going out on a low, in some ways,” Professor O’Malley said, pointing to Mr. Varadkar’s own resignation speech as evidence of that. “There’s a real sense of a party that is exhausted.”
In the past few months, about a third of Fine Gael’s members of Parliament have announced that they are retiring from politics before the 2025 election.
And while there is no clear successor waiting in the wings, Mr. Varadkar may have decided to resign because he believed “a younger, more vibrant leader might be the best chance for that party to try and present a new picture,” Professor O’Malley added.
Mr. Varadkar first became prime minister in 2017 after his predecessor, Enda Kenny, resigned over his handling of a corruption scandal.
A former health minister, he oversaw a 2018 referendum that rolled back the country’s ban on abortion, one of a number of measures that reshaped Ireland’s Constitution in ways that reflected the country’s more secular and liberal modern identity. After the coalition government came to power in June 2020, he served as deputy prime minister before again moving into the leadership role as part of the parties’ power-sharing agreement.
Much of Mr. Varadkar’s work since that time, and in the latter half of his first premiership, focused on navigating a post-Brexit landscape that threatened to undermine the 1998 Good Friday Agreement that had forged decades of peace on the island of Ireland.
He was applauded for those efforts and was seen as crucial to winning major concessions from Britain. Those included negotiating a deal with then Prime Minister Boris Johnson of Britain that avoided a hard border between the Irish Republic and Northern Ireland.
At the start of the coronavirus pandemic, Mr. Varadkar, who had trained as a doctor before becoming a politician, rejoined the medical register to work part time.
But Mr. Varadkar’s return to the political leadership role in 2022 — even after his party had fallen to third place in the last election — had been in many ways an unexpected and challenging second act.
“That’s not the Leo Varadkar that we saw in his previous time in that role,” said David Farrell, a professor of politics at University College Dublin. “The energy had definitely started to go out of it.”
“Suddenly immigration has become a really big topic,” before a general election next year, Professor Farrell said. “We’ve always expected this sort of potential for a far-right agenda to take root here, and we are now beginning to see some of the signs, unfortunately,” he added. Even Sinn Fein, still the most popular party in the polls, has seen its support fall as a result of its policies on immigration, while support for independent candidates who weigh in on immigration has risen.
Mr. Varadkar recently faced criticism for a failed campaign on a double referendum this month that the coalition government had expected to win. Irish voters rejected two proposed changes to the Constitution that would have removed language about women’s duties being in the home and broadened the definition of family beyond marriage.
Analysts said the results partly reflected a weak campaign for the amendments, confusion over the proposals and a lower-than-expected voter turnout that cast a spotlight on the government’s approach.
As he announced his resignation, Mr. Varadkar acknowledged that despite a number of successes, there were “other areas in which we have been much less successful and some in which we have gone backwards.” He said that he would “leave it to others to point them out on a day like this.”
“I know, inevitably, there will be speculation as to the ‘real reason’ for my decision,” he said during the announcement. “These are the real reasons. That’s it. I have nothing else lined up or in mind. No definite personal or political plans, but I am looking forward to having the time to think about them.”
Micheál Martin, the Fianna Fáil leader and deputy prime minister, said on Wednesday that he and Eamon Ryan, the Green Party leader, had been briefed on Tuesday night by Mr. Varadkar about his decision to step down.
“To be honest, I was surprised, obviously, when I heard what he was going to do, but I wanted to take the opportunity to thank him sincerely,” Mr. Martin said.
Mr. Martin said he felt confident that the government had a clear mandate and a clear program for moving forward.
On Wednesday, the news was met mostly with shrugs in Galway, in Ireland’s west, where many hadn’t even heard the news of Mr. Varadkar’s departure. Others, though, saw the unexpected announcement as proof of Ireland’s headwinds.
“The country’s in a right mess,” said Camillus Kelly, 69. He pointed to the housing crisis and strained social service programs as evidence of the issues. His wife has health problems, Mr. Kelly said, and “we have to fight for every bit of support we get.”
Others, though, appreciated Mr. Varadkar’s steady leadership. His long tenure in Irish politics, said Paddi Monaghan, had left a mark, although the resounding “no” votes in this month’s referendums were evidence of the challenges.
“I’m very sad,” said Ms. Monaghan. “I thought he was excellent. It’s not easy, politics today.”
Ali Watkins contributed reporting from Galway, Ireland.
