Meanwhile, the US Supreme Court has rejected Republicans' last-gasp bid to reverse Pennsylvania's certification of President-elect Joe Biden's victory in the electoral battleground state.

President-elect Joe Biden listens during an event at The Queen theater in Wilmington, Delaware, Tuesday, December 8, 2020, to announce his health care team.
President-elect Joe Biden listens during an event at The Queen theater in Wilmington, Delaware, Tuesday, December 8, 2020, to announce his health care team. (AP)

US President-elect Joe Biden has laid out his plan to fight the coronavirus pandemic during his first 100 days in office, saying his administration would vaccinate 100 million Americans, push to reopen schools and strengthen mask mandates.

Biden, who formally introduced his public health team on Tuesday, also announced he would nominate retired Army General Lloyd Austin as the country's first Black defence secretary.

He also picked US Representative Marcia Fudge of Ohio to lead the Department of Housing and Urban Development, and Tom Vilsack, the former agriculture secretary, to fill the same role again, according to news reports on Tuesday.

At a briefing in Wilmington, Delaware, Biden said he needed Congress to fully fund delivering vaccines to all corners of the United States. Getting children back to school will be a national priority in the first 100 days, Biden said.

"In 100 days, we can change the course of the disease and change life in America for the better," said Biden, who takes office on January 20. "Whatever your politics or point of view, mask up for 100 days."

Biden's first few months will likely be dominated by the pandemic, which is straining hospitals amid a nationwide resurgence.

The coronavirus has killed more than 283,000 Americans and caused millions to lose their jobs.

Effective vaccines would help the Biden administration turn its focus to healing the ailing US economy. 

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The US Food and Drug Administration released documents on Tuesday raising no new issues about the safety or efficacy of Pfizer Inc's vaccine, which could receive emergency authorisation this month.

Biden introduced California Attorney General Xavier Becerra, a Latino former congressman, as his nominee for secretary of health and human services. Becerra has a long record of supporting the Affordable Care Act, better known as Obamacare.

High court rejects GOP bid to halt Biden's Pennsylvania win

Meanwhile, the US Supreme Court has rejected Republicans' last-gasp bid to reverse Pennsylvania's certification of President-elect Joe Biden's victory in the electoral battleground.

The court without comment refused to call into question the certification process in Pennsylvania. Democratic Governor Tom Wolf already has certified Biden's victory over President Donald Trump and the state's 20 electors are to meet on Dec. 14 to cast their votes for Biden.

In any case, Biden won 306 electoral votes, so even if Pennsylvania’s results had been in doubt, he still would have more than the 270 electoral votes needed to become president.

READ MORE: Trump seeks appeal of Pennsylvania ruling on election fraud claims

The court's decision not to intervene came in a lawsuit led by Republican US Representative Mike Kelly of northeastern Pennsylvania and GOP congressional candidate and Trump favorite Sean Parnell, who lost to Pittsburgh-area US Representative Conor Lamb, a Democrat.

“Even Trump appointees & Republicans saw this for what it was: a charade,” Lamb said on Twitter.

In court filings, lawyers for Pennsylvania and Gov. Tom Wolf, a Democrat, had called the lawsuit's claims “fundamentally frivolous” and its request “one of the most dramatic, disruptive invocations of judicial power in the history of the Republic.”

“No court has ever issued an order nullifying a governor’s certification of presidential election results,” they wrote.

Republican US Senator Ted Cruz of Texas had offered to argue the case, if the high court took it.

Having lost the request for the court to intervene immediately, Greg Teufel, a lawyer for Kelly and Parnell, said he will file a separate request to ask the court to consider the case on its underlying merits on an expedited basis.

Still, hopes for immediate intervention concerning the November 3 election “substantially dimmed” with the court's action Tuesday, Teufel said.

“But by no way is this over,” Kelly said on Fox News.

Republicans had pleaded with the justices to intervene immediately after the state Supreme Court turned away their case last week.

The Republicans argued that Pennsylvania’s expansive vote-by-mail law is unconstitutional because it required a constitutional amendment to authorize its provisions. Just one Republican state lawmaker voted against its passage last year in Pennsylvania's Republican-controlled legislature.

Biden beat Trump by more than 80,000 votes in Pennsylvania, a state Trump had won in 2016.

Most mail-in ballots were submitted by Democrats.

The state's high court said the plaintiffs waited too long to file the challenge and noted the Republicans' staggering demand that an entire election be overturned retroactively.

In the underlying lawsuit, Kelly, Parnell and the other Republican plaintiffs had sought to either throw out the 2.5 million mail-in ballots submitted under the law or to wipe out the election results and direct the state’s Republican-controlled legislature to pick Pennsylvania’s presidential electors.

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Source: TRTWorld and agencies