“Lot of angst,” said Representative Steve Cohen, Democrat of Tennessee. “We don’t know anything.”

Progressives have signaled they are not inclined to support any deal that cuts domestic spending or imposes stricter work requirements on public benefit programs — both central elements of a deal White House officials and congressional Republicans have been trying to hash out.

Mr. Jeffries says he remains confident that Mr. Biden will not give away the store and will come out of the talks with an agreement palatable to enough House Democrats that it can be approved as long as Mr. McCarthy, a California Republican, and his colleagues provide their share.

“I have full faith in the ability of the Biden administration to lead the charge and protect Democratic values and everyday Americans,” Mr. Jeffries said. “And we’ll be there to support that effort as needed.”

While he is not in the room, Mr. Jeffries is in regular conversation with the White House about what is transpiring, with Jeff Zients, the White House chief of staff, serving as a major point of contact. He credited the administration with engaging with a wide array of House members to prepare them for what is ahead.

“They’ve been open, honest and accessible with House Democrats across the ideological spectrum and that will serve them well at the end of the day when a resolution is reached,” he said.

House Democrats have been grumbling that the White House, not wanting to knock the talks off track, has remained too quiet while Mr. McCarthy and his lieutenants have gathered regularly with reporters, gaining some advantage on the public relations front. Mr. Jeffries has moved to fill that gap in recent days with a series of appearances he has used to assail far-right Republicans, who he accuses of trying to crash the economy for political reasons.

“They’ve decided that either they are able to extract extreme and painful cuts that will hurt everyday Americans or crash the economy and benefit politically in 2024,” he said. “That is unreasonable, it’s cruel, it’s reckless and it’s extreme. But it is the modern-day Republican Party in the House of Representatives.”