WASHINGTON (Reuters) -U.S. President Joe Biden ended his reelection campaign on Sunday after fellow Democrats lost faith in his mental acuity and ability to beat Donald Trump, but did not immediately endorse Vice President Kamal Harris to replace him as candidate.
Biden, 81, in a post on X, said he will remain in his role as president and commander-in-chief until his term ends in January 2025 and will address the nation this week.
"It has been the greatest honor of my life to serve as your President. And while it has been my intention to seek reelection, 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," Biden wrote.
His move could clear the way for Harris to run at the top of the ticket, the first Black woman to do so in the country's history. But Biden did not mention her in his announcement.
It was unclear whether other senior Democrats would challenge Harris for the party's nomination, who was widely seen as the pick for many party officials - or whether the party itself would choose to open the field for nominations.
Biden's announcement follows a wave of public and private pressure from Democratic lawmakers and party officials to quit the race after his shockingly poor performance in a June 27 televised debate last month against Republican rival Trump, 78.
Biden's failure at times to complete clear sentences took the public spotlight away from Trump's performance, in which he made a string of false statements, and trained it instead on questions surrounding Biden's fitness for another 4-year term.
Days later he raised fresh concerns in an interview, shrugging off Democrats' worries and a widening gap in opinion polls, and saying he would be fine losing to Trump if he knew he'd "gave it my all."
His gaffes at a NATO summit - invoking Russian President Vladimir Putin's name when he meant Ukrainian President Volodymyr Zelenskiy and calling Harris "Vice President Trump" -further stoked anxieties.
Only four days before Sunday's announcement, Biden was diagnosed with COVID-19 for a third time, forcing him to cut short a campaign trip to Las Vegas. More than one in 10 congressional Democrats had called publicly for him to quit the race.
Biden's historic move -- the first sitting president to give up his party's nomination for re-election since President Lyndon Johnson in March 1968 -- leaves his replacement with less than four months to wage a campaign.
(Reporting by Kanishka Singh, Jeff Mason, Jarrett Renshaw and Steve Holland, Leah Douglas, Susan Heavey and Tyler Clifford; writing by Scott Malone; Editing by Heather Timmons, Daniel Wallis and Howard Goller)