Video report by Emma Murphy, ITV News correspondent
George W. Bush described the president-elect Joe Biden as a “good man” and called the US elections “fundamentally fair”.
In a statement, the former US leader said he congratulated Biden and Kamala Harris on his historic run for vice-president.
Mr Biden took the victory after winning the key Pennsylvania battlefield on Saturday – about four days after the polls closed – pushing it above the 270-vote threshold in constituencies.
Congratulatory messages have been sent from world leaders around the world in the past 24 hours – and now another former president has personally contacted.
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He said: “Although we have political differences, I know Joe Biden is a good man, who has earned his chance to lead and unify our country.
“The president-elect reiterated that if he runs as a Democrat, he will rule for all Americans.
“I offered him the same thing that I offered to Presidents Trump and Obama: my prayers for his success and my promise to help in any way I could. “
Mr Bush has said Donald Trump has the right to demand recounts and initiate legal action, praising him for his “hard-won campaign.”
The president has been seen playing golf for the second day in a row and does not appear to show any sign of conceding the election anytime soon.
In the statement, he added, “He won the votes of over 70 million Americans – an extraordinary political achievement.
“They have spoken and their voices will continue to be heard by Republicans elected to all levels of government.
“The fact that so many of our citizens participated in this election is a positive sign of the health of our democracy and a reminder to the world of its strength.
“No matter how you voted, your vote counted.
“President Trump has the right to call for recounts and to initiate legal proceedings, and all unresolved issues will be properly addressed.
“The American people can be confident that this election was fundamentally fair, their integrity will be maintained, and the outcome is clear. “
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The president-elect has started working on a plan that he hopes will help heal the United States.
He defined four priorities: the fight against the coronavirus, the reconstruction of the economy, racial justice and climate change.
He pledged on Saturday night to be a president who “seeks to unify” in his first speech as president-elect.
The Democratic nominee has vowed to be the president of all Americans, regardless of their vote, after defeating Donald Trump in the White House race.Mr. Biden told the crowd in Delaware, “I am honored by the trust you have placed in me.“I pledge to be a president who does not seek to divide, but to unify. Who does not see the red and blue states, sees only the United States.
“And who will work with all my heart to earn the trust of all of you, and that’s what America is for, I believe.”