Swathes of A-list actors, singers and other celebrities have come out in force to throw their support behind vice president Kamala Harris after Joe Biden announced his withdrawal from the US presidential race.

Mr Biden ended his bid for re-election on Sunday amid mounting pressure to step aside following the June 27 debate with Republican rival Donald Trump.

The 81-year-old, who said his presidency had been the “greatest honour” of his life, plans to serve out the remainder of his term in office, which ends at noon on January 20 2025.

He has offered his “full support” to Ms Harris to be the Democrat nominee.

Star Trek actor George Takei led a wave of celebrity responses to Mr Biden’s announcement, calling the President a “patriot” and urging people to “unite behind Kamala Harris”.

He wrote on X, formerly Twitter: “I want to honour our President Joe Biden. He has served our nation admirably for decades, he is a decent honorable man, a hugely successful president, and a patriot. Now let us unite behind Kamala Harris and defeat Donald Trump in November!”

Freaky Friday actress Jamie Lee Curtis said the vice president was “trusted and tested”.

In a post to Instagram she said: “I support wholeheartedly @joebiden and his decision to step down and to endorse unreservedly @kamalaharris.

“She is trusted and tested and she is a fierce advocate for women’s rights and people of colour and her message is one of hope and unity for America at her time of great national divide.”

Grammy winning singer John Legend posted a statement alongside an Instagram post calling for the American public to “elect Kamala Harris as our President”.

“She’s ready for this fight and I’m excited to help her in any way I can,” Legend said.

Abbott Elementary star Sheryl Lee Ralph, who attended a star-studded Democrats fundraiser only weeks ago for Mr Biden, posted a photo of herself and Ms Harris, writing: “President Biden has endorsed Kamala Harris!”

Singer Katy Perry responded to Mr Biden’s announcement by singing a few bars from her recently released track Woman’s World.

“It’s a woman’s world, and you’re lucky to be living in it,” she sang in a video posted on Instagram.

Just hours before Mr Biden announced he was ending his re-election bid, West Wing creator Aaron Sorkin said in a New York Times opinion piece that the Democrats should instead select Republican Mitt Romney if the party hoped to defeat Mr Trump, arguing the selection would be “a clear and powerful demonstration” about “stopping a deranged man from taking power.”

However, once Mr Biden confirmed he was dropping out of the race, Sorkin retracted his words – by borrowing the X account of West Wing star Joshua Malin – to instead endorse Ms Harris.

Words shared by the West Wing creator said: “I take it all back. Harris for America!”

Documentary filmmaker Ken Burns wrote on social media: “History recognizes actions that are bigger than self.

“Joe Biden will go down as one of the great ones, having led the country out of the disastrous term of his predecessor and quietly doing good things for all Americans, red state as well as blue, accomplishments that put him up there, in terms of legislative action, with LBJ and FDR.”

He added: “Joe, I can’t imagine where we’d be without your selfless service.”

Actor and director Jon Favreau praised Mr Biden’s decision on Sunday to step down as a “courageous and selfless act”.

Meanwhile, Hocus Pocus star Bette Midler called Mr Biden a “true American patriot”, writing on X: “He’s been a fantastic President, and it hurts that the circumstances have been so unique and historic that he was obliged to drop out. He is the rarest of politicians, a decent man who lived by his values.”

She also called Republican presidential nominee Mr Trump a “schmuck” for his response to Mr Biden’s announcement, in which he called Mr Biden “the worst” president in US history.

Midler said: “So of course, the ever gracious Trump gives Biden another kick with his hobnailed boot as Biden steps down: ‘Joe Biden was the worst president in history’…but as we all know, with DJT, every accusation is a confession. Thanks for the confirmation, schmuck!”

US talk show host and comedian Jon Stewart reacted with a simple, one-word post to X shortly after the President’s announcement.

“Legend,” he wrote.

In a post to X, Star Wars actor Mark Hamill, 72, said: “Joe Biden has a record of accomplishments unmatched by any president in our lifetime.

“He restored honesty, dignity and integrity to the office after four years of lies, crime, scandal and chaos.

“Thank you for your service, Mr President. It’s now our duty as patriotic Americans to elect the Democrat who will honour and further your legacy.”

Funny Girl star Barbra Streisand, 82, said in a post to X: “Joe Biden will go down in history as a man who accomplished significant achievements in his four-year term.

“We should be grateful for his upholding of our democracy.”

Former chat show host Ellen DeGeneres said she was “grateful to President Biden for everything he’s done” while comedian Amy Schumer said she was “all in” for Ms Harris.

Elsewhere, pop star Ariana Grande shared Mr Biden’s post endorsing Ms Harris as the new nominee of the Democratic Party.

Singer Cher wrote on X that it was time for the Democrats to think “way outside the box” and proposed a split ticket.

She wrote: “In my heart im tortured, Because I Don’t believe the Democrats Can win the Presidency With Pres Biden Joe whom I’ve Loved since we met in 2008. I Campaigned for him I believe ITS TIME 2 PASS THE BATON. TIME 4 DEMS 2 THINK “ WAY” OUTSIDE THE BOX. MAYBE EVEN A SPLIT TICKET.”

Marvel star Mark Ruffalo shared a social media statement urging Americans to say no to “the right-wing Christian religious takeover of our nation.”

He wrote on X: “Okay everybody, now we have our marching orders and time to hit the trail running. No to Trump/Vance. No to the right-wing Christian religious takeover of our nation. Nothing wrong with Christianity; just shouldn’t be running a nation birthed from freedom of religion.”

A number of celebrities, including long-time Democrat George Clooney, had called for Mr Biden to drop out of the race days after his debate against former president Mr Trump last month in which he gave a string of nonsensical answers.

In a social media post, Hamill said that “one off night” did not “change the fact that Joe Biden is the most legislatively successful” president “in our lifetime”.

Ocean’s Eleven star Clooney, however, said in a New York Times opinion piece that the party would lose the presidential race as well as any control in Congress with him as the nominee.