Senior members of the Democratic Party have lavished praise on Joe Biden after the US president announced he would not be seeking a second term in the White House.
Mr Biden said it was in the “best interest of my party and the country for me to stand down”.
Barack Obama said the man who served as his vice president was a “patriot of the highest order”.
He said Mr Biden 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 that the Democratic Party would be “navigating uncharted waters in the days ahead”.
But he added: “But I have extraordinary confidence that the leaders of our party will be able to create a process from which an outstanding nominee emerges.”
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”.
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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”.
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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 – as has Mr Biden.
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.”
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