During his address Thursday, Biden announced his first joint session of Congress will take place next month, where he will address the second pillar of his recovery plan, focused on investments in infrastructure.

The president-elect praised Congress for working across the aisle to pass a COVID-19 relief bill in December, but reiterated his message that the package by itself was only a "down payment." He said more is required, framing his policy proposal as the next step and urging lawmakers to push forward.

After blasting the current administration's vaccine distribution plan as a "dismal failure," Biden previewed his remarks Friday, where he plans on laying out his vaccination plan.

"We'll have to move heaven and Earth to get more people vaccinated, to create more places for them to get vaccinated, to mobilize more medical teams to get shots in people's arms, to increase vaccine supply and to get it out the door as fast as possible," he said.

-ABC News' John Verhovek, Molly Nagle, Averi Harper and Beatrice Peterson

Sen. Bernie Sanders issued a statement in support of Biden's COVID Rescue Plan, calling it a "very strong first installment," hinting that he believes more should be done in the future. It could serve as an indication of how the plan will be received by the progressive wing of the Democratic Party.

"President-Elect Biden has put forth a very strong first installment of an emergency relief plan that will begin to provide desperately needed assistance to tens of millions of working families facing economic hardship during the pandemic," Sanders said Thursday in the statement.

"The president-elect's COVID-relief plan includes many initiatives that the American people want and need, including increasing the $600 direct payments to $2,000, and raising the minimum wage to $15 an hour," he added. "As the incoming Chairman of the Senate Budget Committee, I look forward to working with the president-elect and my colleagues in Congress to provide bold emergency relief to the American people as soon as possible."

-ABC News' Averi Harper

Biden, in an evening address from Wilmington, Delaware, is announcing his vaccination and economic rescue legislative package.

The ambitious $1.9 trillion proposal focuses on stimulus amid the ongoing pandemic.

Biden's plan would dedicate more than $1 trillion of the $1.9 trillion price tag for direct stimulus, officials said, while $400 billion would go toward COVID-related projects, including the nationwide vaccination program, and $440 billion toward relief for communities and businesses.

The plan includes direct payments of up to $1,400 to families in need, that when combined with the recent $600 stimulus payment would deliver on Biden's pledge to pass $2,000 of direct payments, along with a $400 weekly unemployment insurance benefit through September and a child tax credit.

-ABC News' Molly Nagle

Photos show the beginning of the process to move President Donald Trump out of the White House, as workers load boxes on to trucks.

Addressing the coronavirus pandemic, confronting the climate crisis and building public trust in science and technology will be among the Biden administration's key areas of focus, the president-elect said during a press briefing introducing four key members of his science team.

Building back the economy "to ensure prosperity is fully shared all across America" and ensuring the U.S. "leads the world in technologies and industries that the future" will also be a focus, Biden said Saturday during an address in Wilmington, Delaware.

Helping lead those initiatives will be Eric Lander, the presidential science advisor-designate, a position that for the first time will be a cabinet rank, Biden noted.

"I've always said that the Biden-Harris administration will lead with science and truth," Biden said. "We believe in both. This is how we're going to, God willing, overcome the pandemic and build our country back better than it was before. That's why for the first time in history, I'm going to be elevating the presidential science advisor to a Cabinet rank, because we think it's that important."

Frances Arnold and Maria Zuber will be at the helm of the first all-women team to lead the President’s Council of Advisors on Science and Technology.

Alondra Nelson will also be deputy director for science and society for the Office of Science and Technology Policy.

Dr. Francis Collins, who was not present at the event, will also continue in his role as director of the National Institutes of Health.Biden thanked him for "being willing to stay on," saying that it wasn't his original plan.

"I've known Dr. Collins for many years. I worked with him closely," Biden said, accling him "brilliant, a pioneer, a true leader."

"This is the most exciting announcement that I have gotten to make in the entire Cabinet," Biden said of his picks. "These are among the brightest, most dedicated people, not only in the country but the world."