WILMINGTON, Del. (AP) — President-elect Joe Biden is calling on Congress to enact billions of dollars in emergency COVID-19 assistance before the year's end, according to a senior adviser who warned Friday that "there's no more room for delay."

Biden transition aide Jen Psaki delivered the remarks before Biden's first in-person meeting since winning the election with House Speaker Nancy Pelosi and Senate Democratic leader Chuck Schumer. The incoming Democratic president hosted the top Democrats in the House and Senate on Friday afternoon at his makeshift transition headquarters in a downtown Wilmington, Delaware, theater.

Biden sat with Schumer, Pelosi and Vice President-elect Kamala Harris, all wearing masks and spaced out around a bank of tables.

"In my Oval Office, mi casa, you casa," Biden said during the brief portion of the meeting that journalists were allowed to witness. "I hope we're going to spend a lot of time together."

Pelosi said at an earlier news conference that she and Schumer would be talking with Biden about "the urgency of crushing the virus," as well as how to use the lame-duck session of Congress, legislation on keeping the government funded and COVID-19 relief.

But prospects for new virus aid this year remain uncertain. Pelosi said talks with Senate Majority Leader Mitch McConnell and GOP leadership on Thursday did not produce any consensus on a new virus aid package.

"That didn't happen, but hopefully it will," she said.

Also Friday, McConnell, a Kentucky Republican, proposed that Congress shift $455 billion of unspent small-business lending funds toward a new COVID-19 aid package. His offer came after a meeting with Treasury Secretary Steven Mnuchin and White House chief of staff Mark Meadows.

Biden's new governing team is facing intense pressure to approve another COVID-19 relief bill and come up with a clear plan to distribute millions of doses of a prospective vaccine, even as Biden is just days away from unveiling the first of his Cabinet picks, which are subject to Senate confirmation.

Psaki said that Biden, Pelosi and Schumer are already working together to push for a pandemic relief bill before Congress adjourns for the year.

"They're in lockstep agreement that there needs to be emergency assistance and aid during the lame-duck session to help families, to help small businesses," Psaki said. "There's no more room for delay, and we need to move forward as quickly as possible."

The president-elect has also promised to work closely with Republicans in Congress to execute his governing agenda, but so far, he has focused his congressional outreach on his leading Democratic allies.

The meeting came two days after House Democrats nominated Pelosi to be the speaker who guides them again next year as Biden becomes president, though she seemed to suggest these would be her final two years in the leadership post.

President Donald Trump continues to block a smooth transition of power to the next president, refusing to allow his administration to cooperate with Biden's transition team. Specifically, the Trump administration is denying Biden access to detailed briefings on national security and pandemic planning that leaders in both parties say are important for preparing Biden to govern immediately after his Jan. 20 inauguration.

Trying to bypass the Trump administration altogether, Biden on Thursday met virtually  with a collection of leading Republican and Democratic governors.

"Unfortunately, my administration hasn't been able to get everything we need," Biden told the National Governors Association's leadership team as he vowed to rise above politics in a unified front against the virus. "There's a real desire for real partnership between the states and the federal government."

The Trump administration's Health and Human Services Secretary Alex Azar said Friday on "CBS This Morning" that Biden's charge that the transition delays would cost American lives is "absolutely incorrect."

"Every aspect of what we do is completely transparent — no secret data or knowledge," Azar said.

Trump, meanwhile, is intensifying his brazen attempts to sow doubt on the election results. The outgoing president's unprecedented campaign to spread misinformation now includes pressuring Michigan officials to block the certification of their state's election results.

Biden won Michigan by more than 150,000 votes, a margin 15 times larger than Trump's victory in the state four years ago.

Election law experts see Trump's push as the last, dying gasps of his campaign and say Biden is certain to walk into the Oval Office come January. But there is great concern that Trump's effort is doing real damage to public faith in the integrity of U.S. elections.

___ Associated Press Congressional Correspondent Lisa Mascaro contributed to this report from Washington.