Election 2024 updates: With Arizona, Trump sweeps all 7 swing states

In the days before the election, senior administration officials insisted that Biden was at peace with his decision to leave the presidential race and had no regrets.

Biden dropped out of the race in July and then endorsed Harris -- a decision the senior administration official said the president made in the days before while in Rehoboth Beach, Delaware.

After Trump's defeat of Harris, many have pointed fingers at Biden -- expressing frustration about his decision to seek reelection until this summer.

After Biden left the race, Harris and the president only did one campaign stop together on Labor Day.

Biden is set to speak to the nation from the White House on Thursday morning.

Biden in a statement on Wednesday said that adding Harris to his 2020 Democratic ticket was the first and "best decision" he made in that campaign. He praised Harris, saying she had "stepped up and led a historic campaign" under extraordinary circumstances.

That statement made no mention of Trump, the former Republican president and now president-elect, who will bookend Biden's sole term in office.

Read more here and watch Biden's speech live on ABC News Live and on the ABC News website.

President Xi Jinping called Donald Trump to congratulate him on his election as the president of the United States, according to state-run Xinhua News Agency.

During the call, Xi said a healthy and sustainable relationship is in the common interests of the two countries, according to the statement.

Vice President Han Zheng also called JD Vance to congratulate him on the election, the report stated.

-ABC News' Karson Yiu

The NAACP organization will seek common ground to work with President-elect Donald Trump's administration, President Derrick Johnson said in a statement.

In the 2024 election cycle, the NAACP spent $20 million to get out the vote and mobilize 14.5 million Black voters.

While the organization did not and does not endorse candidates, the group has agreed to work to advance policies that they believe support the advancement of Black and Brown Americans.

"Our resolve remains stronger than ever as we advocate for policies that dismantle systemic injustices and support the American dream. This new chapter presents an opportunity to chart a course that unites Americans through integrity, understanding, and inclusion," Johnson said on Wednesday.

"Where there is common ground, we will strive to collaborate with the President-elect and his administration. The NAACP is loyal not to politicians, but to policies that allow us to keep advancing, no matter what," Johnson added.

-ABC News' Beatrice Peterson