Joe Biden said the "soul of America" is at stake in his first speech since dropping out of the United States presidential race, in which he defended his political record and reiterated his support for vice-president Kamala Harris' White House bid.
Biden, who has been recovering from COVID-19, addressed Americans from the White House Oval Office on Wednesday evening local time (Thursday AEST).
The 81-year-old on Sunday (local time). He believed his presidential record had put him in good stead for a second term, but had concluded it was time for "new, fresh, younger voices".
"I believe my record as president, my leadership in the world, my vision for America's future, all merited a second term," Biden said.
"But nothing can come in the way of saving our democracy; that includes personal ambition.
"I have decided the best way forward is to pass the torch to a new generation."
Biden again threw his support behind vice-president Kamala Harris. She , which would see her go up against at the November election. Biden described her as "experienced, tough, and capable".
He said his country was at an "inflection point" and the result of the election would "determine the fate" of the US and the world "for decades to come".
"America will have to choose between moving forward or backward, between hope and hate, unity and division," Biden said.
"We have to decide, do we still believe in honesty, decency, respect, freedom, justice, and democracy?"
Biden reiterated that he would continue to serve his country over the next six months, setting out an agenda that included securing the safe return of Israeli hostages, taken by militant group Hamas , and Supreme Court reform.
President Joe Biden has endorsed Kamala Harris as the Democratic nominee to go up against Republican candidate Donald Trump. Source: AAP, AP / Patrick Semansky
The court — which has a conservative majority, including three justices appointed during Trump's term as president — has been in the spotlight over a number of major rulings.
These include , a move that made it the responsibility of states to decide whether abortion is legal.
Biden also defended his term in office, including his administration's handling of the economy, its approach to tackling crime, and its response to crossings at the US' southern border with Mexico.
"I ran for president four years ago because I believed and still do that the soul of America is at stake," Biden said. "The very nature of who we are was at stake and that is still the case."
He finished his address by stating that "kings and dictators do not rule" America, "the people do".
"The power is in your hands. The idea of America lies in your hands ... So let's act together and preserve our democracy."
The Democratic National Committee's rules committee agreed on Wednesday on a plan to formally nominate Harris as soon as 1 August — before the party's August 19-22 convention in Chicago — with Harris picking a running mate by 7 August.
Earlier on Wednesday, the 59-year-old vice-president called on a rally of more than 6,000 black women in Indianapolis to help her revitalise the Democratic campaign.
Harris spoke at an event in Indianapolis hosted by the Zeta Phi Beta Sorority, which was founded at Howard University, the historically black college she attended.
She hopes to tap sororities' multi-generational network of black women — who played an important role in Biden's 2020 victory — to deliver strong voter turnout for Democrats again in November.
"I thank you. And now, in this moment, our nation needs your leadership once again," Harris said.
Trump, coming off a triumphant week in which his party unified around his presidential bid , has had to watch as Biden's sudden departure from the race shifted the narrative and sparked a surge of attention toward Harris at his expense.
Harris and Trump are closely competitive, public opinion polls showed this week.
A Reuters/Ipsos poll completed on Tuesday showed Harris with a marginal two-percentage-point lead over Trump, 44 per cent to 42 per cent.
A CNN poll conducted by SSRS showed Trump leading Harris, 49 per cent to 46 per cent. Both findings were within the polls' margins of error.
With reporting by Reuters via the Australian Associated Press.
