President Joe Biden and House Speaker Kevin McCarthy spoke directly Saturday evening as they worked to reach an agreement that would resolve the looming debt crisis ahead of a June 5 deadline and avert a catastrophic U.S. default.

Biden spoke earlier in the day with Democratic leaders in Congress to discuss the status of the talks, according to three people familiar with the situation, who spoke on condition of anonymity because they were not authorized to discuss the matter publicly. But the two sides have not reached a deal yet.

'Big, thorny issues remain,' one of the top negotiators, Representative Patrick McHenry, R-N.C., told reporters in the evening.

The Republican House speaker gathered top allies behind closed doors at the Capitol as negotiators pushed for a deal that would raise the nation's borrowing limit and avoid a default on the nation's debt, while also making spending cuts that House Republicans are demanding.

As he arrived at the Capitol early in the day, McCarthy said that Republican negotiators were 'closer to an agreement.'

McCarthy's comments echoed the latest public assessment from Biden, who said Friday evening that bargainers were 'very close.'

Treasury Secretary Janet Yellen told Congress on Friday that the United States could default on its debt obligations by June 5 - four days later than previously estimated - if lawmakers do not act in time to raise the federal debt ceiling. The extended deadline gives the two sides a bit more time as they scramble for a deal.

But as another day dragged on with the country watching and waiting for an outcome, it appeared some of the problems over policy issues that have dogged talks all week remained unresolved.

Both sides have suggested one of the main holdups is a GOP effort to expand existing work requirements for recipients of food stamps and other federal aid programs, a longtime Republican goal that Democrats have strenuously opposed. The White House said the Republican proposals were 'cruel and senseless.'

They also appear to be laboring over a compromise on changes to federal permitting that would ease regulations for developing oil, gas and renewable energy projects and foster new transmission line connections.

Americans and the world were uneasily watching the negotiating brinkmanship that could throw the U.S. economy into chaos and sap world confidence in the nation's leadership. House negotiators left the Capitol at 2 a.m. the night before, only to return hours later.

Failure to lift the borrowing limit, now $31 trillion, to pay the nation's incurred bills, would send shockwaves through the U.S. and global economy. Yellen said failure to act by the new date would 'cause severe hardship to American families, harm our global leadership position and raise questions about our ability to defend our national security interests.'

Anxious retirees and others were making contingency plans for missed checks, with the next Social Security payments due next week.

The president, spending part of the weekend at Camp David, talked with his negotiating team multiple times a day, signing off on offers and counteroffers. Biden was upbeat as he departed the White House on Friday evening, saying: 'It's very close, and I'm optimistic.'

Biden and McCarthy have seemed to be narrowing on a two-year budget-cutting deal that would also extend the debt limit into 2025 past the next presidential election. The contours of the deal have been taking shape to cut spending for 2024 and impose a 1% cap on spending growth for 2025.

Any deal would need to be a political compromise in a divided Congress. Many of the hard-right Trump-aligned Republicans in Congress have long been skeptical of the Treasury's projections, and they are pressing McCarthy to hold out.

The Republican proposal on work requirements would save $11 billion over 10 years by raising the maximum age for existing standards that require able-bodied adults who do not live with dependents to work or attend training programs.

Current law applies those standards to recipients younger than 50. The GOP plan would raise the age to include adults 55 and younger. It would lower the number of exemptions that states can grant to some recipients subject to those requirements.

Biden has said the work requirements for Medicaid would be a nonstarter. He initially seemed potentially open to negotiating minor changes on food stamps, now known as the Supplemental Nutrition Assistance Program, or SNAP, but his position has appeared to harden.

Lawmakers are not expected to return to work from the Memorial Day weekend before Tuesday, at the earliest, and McCarthy has promised lawmakers he will abide by the rule to post any bill for 72 hours before voting.

The Democratic-held Senate has largely stayed out of the negotiations, leaving the talks to Biden and McCarthy. Senate Majority Leader Chuck Schumer of New York has pledged to move quickly to send a compromise package to Biden's desk.