U.S. President-elect Joe Biden's top advisers on Sunday outlined his plans to tackle the nation's multiple crises while balancing the impeachment trial of the nation's president Donald Trump, as an historic inauguration week opens in the United States.

Washington was under the watch of thousands of National Guard troops and ringed with security barriers ahead of Biden's swearing on Wednesday, in a nation still rattled by the January 6 attack on the Capitol.

"I hope that the Senate leaders on a bipartisan basis have found a way to move forward on all their responsibilities," including the impeachment trial and dealing with the coronavirus pandemic, Biden's incoming chief of staff Ron Klain told CNN.

But injecting a note of urgency, he warned that the nation could reach the awful total of 500,000 COVID-19 deaths sometime next month. The toll on Sunday surpassed 397,000, according to a tally from Johns Hopkins University.

As the president-elect prepares to take power in a city where only two weeks earlier Trump supporters launched a violent attempt to overturn the election, Biden faces overlapping crises: not only the pandemic but a struggling economy, climate change and racial tensions.

Biden wants the Congress to act quickly on a massive, $1.9 trillion stimulus plan to revive the economy, and he plans a blitz to accelerate America's stumbling coronavirus vaccine rollout.

His target of seeing 100 million doses of COVID-19 vaccine injected within his first 100 days in office is "absolutely" achievable, top U.S. scientist Anthony Fauci told NBC on Sunday.

"The feasibility of his goal is absolutely clear, there's no doubt about it," said Fauci, who will be Biden's chief adviser on the coronavirus, as he was Trump's.

Shadow of uncertainty 

The lead prosecutor for Trump's historic second impeachment has started building his case for conviction at trial, asserting on Sunday that the outgoing president's incitement of the rioters that stormed the U.S. Capitol was "the most dangerous crime" ever committed by a president against the nation. A Senate trial could begin as soon as this week, just as Biden is sworn in as the 46th president.

Democratic congressional leaders Nancy Pelosi and Chuck Schumer have yet to say when the trial against Trump for "incitement of insurrection" will begin.

"I don't think there's any promised date when Speaker Pelosi is going to present the articles of impeachment," Dick Durbin, a Democratic leader in the Senate, told CNN. But Representative Jamie Raskin said "it should be coming up soon" as Pelosi organizes the formal transfer.

The House voted to impeach Trump last Wednesday, one week after the violent insurrection that interrupted the official count of electoral votes, ransacked the Capitol and left Congress deeply shaken. Before the rioters overpowered police and entered the building, Trump told them to "fight like hell" against the certification of Biden's election win.

"We're going to be able to tell the story of this attack on America and all of the events that led up to it," Raskin said. "This president set out to dismantle and overturn the election results from the 2020 presidential election. He was perfectly clear about that."

Democrats and the incoming administration are facing the challenge of reckoning with the Capitol attack at the same time that Biden takes office and tries to move the country forward. They say the Congress can do both, balancing a trial with confirmations of the new president's Cabinet and consideration of his legislative priorities.

'Socialized policy'

One frequent Trump confidant, Senator Lindsey Graham, warned Sunday on Fox News' Sunday Morning Futures that Republicans may not offer Biden much of a grace period, if any – saying the president-elect might be trying to move too far too fast.

"I think we are going to have in the first hundred days by the Biden administration the most aggressive socialized policy effort in the history of the country," he said. "No good comes from impeaching President Trump (when he is) out of office."

But Klain repeated Biden's affirmation that the Senate – controlled only narrowly by Democrats – could handle both an impeachment trial and the new Biden agenda. He added Biden would be able to take a flurry of executive actions – requiring no congressional approval – as early as Wednesday afternoon.

They will include returning the country to the Paris climate accord and ending the travel ban on some mainly Muslim countries.

Plans for the inauguration – in normal times a bracing, even joyous, tribute to peaceful transition – had already been scaled down out of pandemic concerns. Fears of new violence by unyielding Trump supporters after the January 6 riot have cast a further pall.

"This will be an inaugural like no other, in large part because of COVID-19," Vice President-elect Kamala Harris said in an interview aired Sunday on CBS.

"But we are going to get sworn in. And we're going to do the job we were hired to do."

(With input from AP and AFP)