President Donald Trump's desperate bid to overturn the November 3 election result was dealt another blow on Friday after it was announced he had lost Georgia, while the winner, President-elect Joe Biden, filled more jobs in his incoming US administration.

Biden, a Democrat, is preparing to take office on January 20, but Trump, a Republican, has refused to concede and is seeking to invalidate or reverse the results through lawsuits and recounts in a number of states, claiming - without proof - widespread voter fraud.

That effort - which Trump's critics have called an unprecedented push by a sitting president to subvert the will of the voters - has met with little success. Trump's campaign has suffered a string of legal defeats and apparently has failed to convince fellow Republicans in states that he lost, such as Michigan, to act on his unfounded conspiracy theories.

It received more bad news on Friday when Georgia Secretary of State Brad Raffensperger announced that a manual recount and audit of all ballots cast in the southern state had determined that Biden was the winner.

Biden is the first Democrat to carry Georgia since 1992.

"The numbers reflect the verdict of the people, not a decision by the secretary of state's office or courts, or of either campaign," Raffensperger, a Republican and Trump supporter, told reporters. Official figures on the Secretary of State's website showed Biden winning the state by 12,670 votes.

Georgia Governor Brian Kemp, a Republican, said he was required by law to formalize the certification of the results, "which paves the way for the Trump campaign to pursue other legal options in a separate recount if they choose." But he also said the audit showed some errors in the original vote count.

Trump had earlier expressed dismay, saying on Twitter that Georgia officials were refusing "to let us look at signatures which would expose hundreds of thousands of illegal ballots" and give him and his party "a BIG VICTORY."

The president provided no evidence to back up his claim.

Trump, in his first public comments in days about the election outcome, again asserted "I won" as he strayed from the theme of a White House event on lowering drug prices. But he also seemed to acknowledge the possibility he might not stay in power, saying pharmaceutical companies had opposed his pricing reform and, "I just hope they keep it."

Stung by a series of court defeats, the Trump team is resting its hopes on getting Republican-controlled legislatures in battleground states won by Biden to set aside the results and declare Trump the winner, according to three people familiar with the plan.

It is focusing on Michigan and Pennsylvania for now, but even if both those states flipped to the president he would need to overturn the vote in another state to vault ahead of Biden in the Electoral College.

Such an extraordinary event would be unprecedented in modern US history. Trump not only would need three state legislatures to intervene against vote counts as they stand now, but then also have those actions upheld by Congress and, almost certainly, the US Supreme Court.

Undeterred by the lengthening odds, Trump invited Michigan's state legislative leaders, Senate Majority Leader Mike Shirkey and House of Representatives Speaker Lee Chatfield, both Republicans, to meet him on Friday at the White House.

In a statement issued after the meeting in the Oval Office, Shirkey and Chatfield said they had discussed how Michigan needed additional federal funding to fight the coronavirus pandemic, and they said they had faith in a review of Michigan's elections process that is being conducted by state lawmakers.

"We have not yet been made aware of any information that would change the outcome of the election in Michigan and as legislative leaders, we will follow the law and follow the normal process regarding Michigan's electors, just as we have said throughout this election," their statement said.

The White House had no immediate comment.

Arriving at Ronald Reagan Washington National Airport earlier in the day, Shirkey and his colleagues were met by a crowd of demonstrators, some of whom held signs that read "SHAME" while others chanted "respect Michigan voters."

Biden, who turned 78 on Friday, continued to lay the foundation of his administration, announcing appointments including his former deputy chief of staff Louisa Terrell as the incoming director of the White House's office of legislative affairs, the main liaison with Congress.

Biden also met US House of Representatives Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer, the Democratic leaders in Congress, in his home state of Delaware.

They agreed Congress needs to pass an emergency relief package in the current session to blunt the economic pain of the pandemic, according to a joint statement. More than 252,000 people in the United States have died from COVID-19.

'Put the country first'

The president's lawyers argue the US Constitution gives legislatures, rather than state governors and secretaries of state, the ultimate authority to appoint electors. Republicans control the Michigan, Pennsylvania and Wisconsin legislatures.

Those states were the pillars of Trump's victory in the 2016 election, but Biden prevailed in all three by even larger margins than Trump did four years ago.

Legal experts have sounded the alarm at the notion of a sitting president seeking to undermine the will of the voters, though they have expressed skepticism that a state legislature could lawfully substitute its own electors.

Pressure for Trump to start the formal transition process mounted, with a few more Republicans voicing doubts over Trump's claims of fraudulent voting.

US Senator Lamar Alexander of Tennessee, who is retiring at the end of the year, said Biden had a "very good chance" of becoming the next president and that the loser of the election should "put the country first."

There is a "right way and a wrong way" for Trump to contest what he sees as election irregularities, Susan Collins, the Maine Senator, said in a statement. "The right way is to compile the evidence and mount legal challenges in our courts. The wrong way is to attempt to pressure state election officials."

Danielle Friedman, senior counsel for Biden's campaign, told reporters the recount requested by Trump in Wisconsin was on course to reaffirm Biden's "resounding" victory in the state. The official canvass in the state, she said, had put Biden's win at a margin of 20,608 votes.

Nationally, Biden won nearly 6 million more votes than Trump, a difference of 3.8 percentage points. But the outcome of the election is determined in the Electoral College, where each state's electoral votes, based largely on population, are typically awarded to the winner of a state's popular vote.

Biden leads by 306 electoral votes to Trump's 232 as states work to certify their results at least six days before the Electoral College convenes on December 14.