Former President Barack Obama announced his long-expected endorsement of Joe Biden for president, giving a boost to the presumptive Democratic presidential nominee.

“Choosing Joe to be my vice president was one of the best decisions I ever made, and he became a close friend. And I believe Joe has all the qualities we need in a president right now,” the former president said in a video released Tuesday.

He praised his former vice president for making a stunning comeback in the Democratic presidential primaries, alluding to Biden's losses in Iowa and New Hampshire.

"Joe will be a better candidate for having run the gauntlet of primaries and caucuses alongside one of the most impressive Democratic fields ever. Each of our candidates were talented and decent, with a track record of accomplishment, smart ideas, and serious visions for the future," Obama said.

"Right now, we need Americans of goodwill to unite in a great awakening against a politics that too often has been characterized by corruption, carelessness, self-dealing, disinformation, ignorance, and just plain meanness," Obama said. "And to change that, we need Americans of all political stripes to get involved in our politics and our public life like never before."

Biden responded to the endorsement in a tweet.

"Barack — This endorsement means the world to Jill and me. We’re going to build on the progress we made together, and there’s no one I’d rather have standing by my side," he said.

Obama's endorsement comes after Biden's last remaining primary rival, Vermont Sen. Bernie Sanders, endorsed Biden on Monday.

Biden heavily leaned on his connection to Obama in the Democratic primary campaign, repeatedly referring to the "Obama-Biden administration." Biden's supporters often cited his experience as Obama's vice president as a major reason why they thought he should be the party's nominee.

Conservative commentators frequently mocked Biden for failing to secure Obama's endorsement during the Democratic primary, allowing national newcomer Pete Buttigieg to win the Iowa caucuses and failing to win a delegate in the New Hampshire primary.

Biden claimed that he asked Obama not to endorse him before he earned presumptive nominee status. "I asked President Obama not to endorse, and whoever wins this nomination should win it on their own merits," he said the day he announced his candidacy last year.

President Trump chimed in on Obama's absence from the campaign trail shortly after Sanders suspended his campaign, which made Biden the presumptive Democratic presidential nominee.

"I don't know why President Obama hasn't supported Joe Biden a long time ago. There's something he feels is wrong," Trump said.

Obama was reportedly prepared to jump in to stop Sanders from becoming the nominee, but an anonymous source close to Obama told CNN on Super Tuesday in March that the former president was “skeptical that an endorsement coming from us could truly change the political winds right now ... If he were to try to put his thumb on the scale now, it would take away his ability to do so when it’s most needed — the general election.” Obama appeared with Biden when Biden announced he would not seek the 2016 Democratic nomination.

With Obama now fully committed to Biden, he will be able to campaign on his behalf and work to raise money and energize voters to vote against Trump in November.

Obama's backing of his former understudy is not particularly late by historical standards. In 1988, President Ronald Reagan endorsed his vice president, George H.W. Bush, on May 11 of that year, long after competitive Republican primaries wound down.

And, in 1960, outgoing Republican President Dwight D. Eisenhower offered an endorsement of his two-term vice president, Richard Nixon. In January of that year, Eisenhower told the Los Angeles Times, "The only thing I know about the presidency the next time is this — I can't run."

That August, Eisenhower was asked by a reporter to give an idea that Nixon had come up with during his presidency.

"If you give me a week, I might think of one. I don't remember," Eisenhower said.

The Trump campaign responded to news of the endorsement by criticizing Obama.

“Barack Obama spent much of the last five years urging Joe Biden not to run for president out of fear that he would embarrass himself," Brad Parscale, Trump 2020 campaign manager, said in a statement. "Now that Biden is the only candidate left in the Democrat field, Obama has no other choice but to support him. Even Bernie Sanders beat him to it. Obama was right in the first place: Biden is a bad candidate who will embarrass himself and his party. President Trump will destroy him.”





Naomi Lim contributed to this report.