Joe Biden has withdrawn from the 2024 presidential race.
In a development that sends the contest into uncharted territory, the US president announced he will no longer be seeking a second term.
He has thrown his support behind Kamala Harris, urging Democrats to donate to her campaign as he pulled out.
In a letter addressed to “my fellow Americans”, Mr Biden said it had been the “greatest honour of my life to serve as your president”.
“While it has been my intention to seek re-election, I believe it is in the best interest of my party and the country for me to stand down and to focus solely on fulfilling my duties as president for the remainder of my term,” he said.
He endorsed Ms Harris as the Democratic nominee and, referring to his Republican rival, he added: “Democrats – it’s time to come together and beat Trump.”
Follow live: Reaction as Biden pulls out of race
Mr Biden made the announcement in a statement posted on X, in which he said he would address the nation later this week to provide “detail” about his decision.
“For now, let me express my deepest gratitude to all those who have worked so hard to see me re-elected,” he said.
“I want to thank vice president Kamala Harris for being an extraordinary partner in all this work. And let me express my heartfelt appreciation to the American people for the faith and trust you have placed in me.
“I believe today what I always have: that there is nothing America can’t do – when we do it together. We just have to remember we are the United States of America.”
First Lady Jill Biden, whose loyalty to her husband has been unswerving, responded by sharing his statement on X with a simple heart emoji.
Ms Harris, who many are touting as the frontrunner to replace Mr Biden, said she was “honoured” to have the president’s endorsement, adding “my intention is to earn and win this nomination”.
She thanked Mr Biden for his “extraordinary leadership” and for making a “selfless and patriotic act” by stepping aside.
She said: “I will do everything in my power to unite the Democratic Party – and unite our nation – to defeat Donald Trump and his extreme Project 2025 agenda.
“We have 107 days until Election Day. Together, we will fight. And together, we will win.”
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Joe Biden pulls out of 2024 US election
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Mr Biden plans to serve out the remainder of his term in office, which ends at noon on 20 January 2025.
But questions are already being asked about whether he should stand down from the presidency as well as withdrawing from the re-election race.
The Republican House of Representatives speaker Mike Johnson has called on him to resign, saying “if Joe Biden is not fit to run for president, he is not fit to serve as president”.
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A sudden decision after long speculation
The seismic development comes after months of speculation about Mr Biden’s age and fitness to serve another four years – amid a series of high-profile gaffes and a disastrous debate performance.
Democrats described his debate with Mr Trump as an “unmitigated disaster” and “a slow motion car crash” after he appeared incoherent, stumbling over his words and freezing.
Mr Biden, 81, had previously insisted he was best placed to defeat Mr Trump in the upcoming election but had faced calls from within his own party to step aside.
As of Saturday night he had planned to stay in the race, but told senior staff on Sunday afternoon he was withdrawing, a source familiar with the matter said.
The decision caught many White House staff off guard, with several expressing shock the president made the announcement while recovering from COVID at his Delaware home.
Mr Biden spent the 48 hours before the announcement digesting large amounts of data and polls that showed his path to victory was largely out of reach, two sources told Reuters.
He spoke with Ms Harris several times on Sunday ahead of the announcement, according to a source familiar with the conversation.
He agonised over the decision – but once he made up his mind, he moved quickly, a senior White House official said.
He broke the news to his senior team at 1.45pm on Sunday, the sources said – and his bombshell announcement on social media came just one minute later.
A source close to the president recently admitted “we’re close to the end” after Barack Obama, the former president who picked Mr Biden as his vice president during his two terms in office, reportedly shared his concerns about his ally’s re-election bid.
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Trump calls Biden ‘worst president’ in US history
Pic: Reuters
Trump responds to rival pulling out
Donald Trump has reacted to the news, telling Sky News’ US partner NBC News Mr Biden “should never have been” in the race.
“Joe Biden is the worst president in the history of the United States by far,” he said.
“There has never been a president who has done such damage to our country. From energy independence to letting in millions and millions of illegal immigrants.”
Mr Biden’s debate with Mr Trump marked a turning point. Pic: AP
Mr Trump said Ms Harris will be easier to defeat in the race for the White House than Mr Biden.
In a phone call with CNN minutes after Mr Biden’s announcement, Mr Trump said he did not know who he would face, but suggested the vice president would not pose him a bigger problem than the sitting president.
In a post on his Truth Social platform, he said: “Crooked Joe Biden was not fit to run for President, and is certainly not fit to serve – And never was!”
Mr Trump claimed Mr Biden “attained” the job as president “by lies, Fake News, and not leaving his Basement”.
Biden endorses Kamala Harris
Attention will now turn to who will succeed him, with the selection likely to happen at the Democratic National Convention in August.
Shortly after announcing he was pulling out, Mr Biden backed his vice president Ms Harris to take his place as the Democratic Party’s nominee for the presidential election.
He thanked her for being “an extraordinary partner” before backing her to take the party’s nomination.
In a statement on X, he said: “Today I want to offer my full support and endorsement for Kamala to be the nominee of our party this year.”
She appears to be the natural successor, in large part because she is the only candidate who can directly tap into the Biden campaign’s war chest, according to federal campaign finance rules.
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Could Kamala Harris be the next US president?
Mr Biden’s backing helps clear the way for her, but a smooth transition is by no means assured.
It remains to be seen whether other candidates could challenge Ms Harris for the nomination, or how party may need to adjust its rules again to smooth Ms Harris’s nomination on the floor.
The Democratic National Committee chair, Jaime Harrison, has promised a “transparent and orderly process” in selecting its next candidate.
He said the Democrats will share more about “next steps and a path forward” shortly, adding: “The work that we must do now, while unprecedented, is clear.”
Obama thanks Biden – but does not endorse Harris
Barack Obama has praised Mr Biden but has not endorsed Mr Harris to lead the Democratic Party.
He said in a statement: “We will be navigating uncharted waters in the days ahead. But I have extraordinary confidence that the leaders of our party will be able to create a process from which an outstanding nominee emerges.”
He called Mr Biden one of “America’s most consequential presidents” as well as being a “dear friend and partner” to him.
