Barack Obama has praised Joe Biden as a "patriot of the highest order", saying the US president had put American interests ahead of his own as he decided not to seek re-election.

Vice-president and potential Democratic nominee Kamala Harris and Bill and Hillary Clinton have also released statements to thank Mr Biden for his years of service.

Mr Biden announced his historic decision earlier on Sunday, bowing to pressure from within his own party after a disastrous debate against Donald Trump.

He said it was in the "best interest of my party and the country for me to stand down".

'Dear friend and partner'

Mr Obama said the man who served as his vice president was a "dear friend and partner".

In both a personal and political statement, he said he and his wife Michelle wanted to thank "Joe and Jill for leading us so ably and courageously during these perilous times".

Mr Biden has a "fundamental decency and belief that everyone counts", Mr Obama added.

He said the president had "passed the first major piece of gun safety legislation in 30 years" while, internationally, he "mobilised the world to stand up against Russian aggression in Ukraine".

Mr Obama admitted the Democratic Party would be "navigating uncharted waters in the days ahead" - and stopped short of endorsing Ms Harris as Mr Biden and other senior Democrats have.

He continued: "But I have extraordinary confidence that the leaders of our party will be able to create a process from which an outstanding nominee emerges."

Ms Harris said she got to know the president "through his son Beau" who she worked with "as attorneys general of our home states".

The vice president said: "The qualities Beau revered in his father are the same qualities, the same values, I have seen every single day in Joe's leadership as president: his honesty and integrity, his big heart and commitment to his faith and his family."

She added: "I am honoured to have the president's endorsement and my intention is to earn and win this nomination."

'Extraordinary' career of service

Former president Mr Clinton and former secretary of state and presidential nominee Mrs Clinton praised Mr Biden's "extraordinary" career of service.

They said he had "lifted America out of an unprecedented pandemic, created millions of new jobs, rebuilt a battered economy, strengthened our democracy, and restored our standing in the world."

Mr Biden's leadership, they added, "advanced our founders' charge to build a more perfect union and his own stated goal of restoring the soul of our nation."

In their joint statement, the Clintons endorsed Ms Harris, saying it was time to "fight with everything we've got" to elect her.

Mr Biden has been an "extraordinary, history-making president", said Gavin Newsom, the governor of California who has been touted as a possible presidential candidate.

He has also "delivered astonishing results for all Americans", Mr Newson said on X, and will "go down in history as one of the most impactful and selfless presidents".

'Vision, values and leadership'

Senate majority leader Chuck Schumer said Mr Biden has "put his country, his party, and our future first".

He added: "Joe, today shows you are a true patriot and great American."

Former House speaker Nancy Pelosi said Mr Biden leaves a "legacy of vision, values and leadership", making him one of the "most consequential presidents in American history".

She added: "God blessed America with Joe Biden's greatness and goodness."

Jaime Harrison, who chairs the Democratic National Committee, said the American people "owe President Biden an enormous debt of gratitude".

He said the party would undertake a "transparent and orderly process" to choose a candidate "who can defeat Donald Trump in November".

Gretchen Whitmer, the governor of Michigan, said Mr Biden had undertaken "remarkable work to lower prescription drug costs, fix the damn roads, bring supply chains home, address climate change, and ensure America's global leadership".

She added that her "job" in the forthcoming election is to do "everything I can to elect Democrats and stop Donald Trump".

Pete Buttigieg, the transport secretary, said Mr Biden had "earned his place among the best and most consequential presidents in American history".

He added: "I am so proud to serve under his leadership, and thankful for his unwavering focus on what is best for our country."

Democratic congresswoman Pramila Jayapal thanked Mr Biden for his "incredible work" and endorsed Kamala Harris as the Democrats' candidate for president.

She wrote on X: "As the first South Asian woman elected to the House of Representatives, I look forward to seeing Kamala Harris become the first South Asian American and first Black woman to serve as the President of the United States of America.

"Democrats must immediately unite so we can focus on winning in November."