WASHINGTON - The Trump administration and congressional Democrats neared agreement Thursday night on an economic relief package to help people impacted by the coronavirus, with both sides under enormous pressure to act to address the spiraling crisis.

Speaker Nancy Pelosi, D-Calif., said she expected a vote Friday "one way or another" to approve the package, which is expected to amount to several tens of billions of dollars.

"We've resolved most of our differences, and those we haven't we'll continue to have a conservation - because there will obviously be other bills," Pelosi told reporters outside of her office in the Capitol, at the end of a long day of intense talks with Treasury Secretary Steven Mnuchin.

The legislation will include measures to boost paid family leave and unemployment insurance, ensure free coronavirus testing, and strengthen nutritional aid like food stamps. The emerging agreement builds upon a bill House Democrats released late Wednesday that included a number of provisions Republicans opposed, setting off hours of frenzied negotiations on Capitol Hill to reach bipartisan consensus.

Lawmakers of both parties were determined to deliver an economic relief package before a congressional recess that had been scheduled for next week. "Let's try to accomplish something that we can agree on and get it done," said Sen. Rob Portman, R-Ohio, summing up the sentiments of many.

A final hang-up was over a paid family and medical leave provision, with Republicans pushing to structure it in a way that it could be implemented quickly and avoid undue burdens on employers.

"There were some differences of opinion, but we felt that putting together something that the American people could see cooperation on between the two parties in this difficult moment, would be a confidence builder," said House Ways and Means Chairman Richard Neal, D-Mass. "And I think that we approached it that way."

While House approval of the package was expected on Friday, clearing lawmakers to begin a scheduled recess, the Senate is not expected to take it up until next week. Majority Leader Mitch McConnell, R-Ky., canceled his chamber's planned recess next week but allowed senators to leave Washington for the weekend.

As originally introduced, the House bill included a $2 billion boost to state unemployment insurance programs, more than $1 billion in nutritional aid, a new paid-leave benefit for employees affected by the outbreak and an increase in federal Medicaid spending, as well as a guarantee of free coronavirus testing. Republicans viewed the initial legislation as overly broad, and President Donald Trump criticized it as full of "the goodies that they haven't been able to get for the last 25 years."

Through hours of phone calls and staff-level negotiations, Pelosi and Mnuchin agreed to narrow the legislation to focus more squarely on impacts from the coronavirus and those hurt by it. The legislative text was still being finalized, but Pelosi said that Mnuchin's suggestions had been "all very reasonable."

The near-deal Thursday evening represented a dramatic turnaround from the state of play in the morning, when the White House and congressional Republicans panned House Democrats' bill and suggested that chances for a quick deal were remote.

But as the hours progressed and the scale of the crisis mounted, it became clear there was no appetite among lawmakers to leave Washington for a week or more without acting.

Only last week Congress passed an $8.3 billion emergency spending plan to address public health needs arising from the crisis. But with the stock market plunging, layoffs beginning, schools around the country shutting down, and entire sports leagues shuttering their seasons, the need for a robust economic response became glaring.

There are now well over 1,000 confirmed coronavirus cases in the U.S. and more than three dozen deaths, numbers that are expected to exponentially rise. And increasing numbers of lawmakers are announcing plans to shut down their offices and self-quarantine following brushes with infected individuals.

"This is such a serious issue," said Sen. Joni Ernst, R-Iowa, who is up for reelection in November. "We need to be continually monitoring this as a group, not having us all out to the four winds."

Trump is advancing costly ideas of his own - including a payroll-tax holiday that could drain tens of billions of dollars from Social Security. That idea has gotten limited traction among both parties on Capitol Hill, and congressional leaders decided to pursue a narrower package that could win GOP support, leaving broader measures, such as the payroll-tax cut, for another day.

The White House was also moving to assemble its own relief plan, one that included requests for congressional action as well as administrative actions that the Trump administration could take unilaterally.

White House officials held meetings Thursday to hammer out details of the administration's economic response package as promised by Trump in his national address Wednesday night, including some kind of paid-sick-leave plan that could be enacted administratively. Critical details remained unresolved, however.

As originally written, the House paid-leave plan relied on a two-pronged approach, combining a temporary program that would be administered by the Social Security Administration that would provide up to $4,000 a month to affected households, with a new permanent sick-leave mandate for U.S. employers. Only firms employing fewer than 50 people would be eligible for federal assistance in meeting that mandate, which was strongly opposed by the administration.

Those plans underwent significant changes over the day of talks, and in the final hours negotiators were haggling over a less ambitious family and medical leave expansion proposal from Rep. Bobby Scott, D-Va., which would expand the number of workers who can take up to 12 weeks of job-protected leave under the Family and Medical Leave Act while drawing down wage replacement. Another idea was to instead use a Small Business Administration program to give employee retention tax cuts to smaller businesses.

"It's about paid sick leave. It's about family and medical leave. It's about unemployment insurance. It's about our children who are out of school and need to be fed. It's about seniors and people with disabilities," Pelosi said. "This goes to the actual heart of what our purpose is."

Another controversial provision in the original bill would have increased the percentage of Medicaid spending borne by the federal government by 8 percentage points through Sept. 30, 2021. That would be a welcome relief to states, which could see an influx of Medicaid enrollees in a time of economic crisis. But the price tag for the federal government could have been vast - stretching easily into the tens of billions of dollars.