President Joe Biden said on Sunday that Republicans in the US House must move off their "extreme positions" on the now-stalled talks over raising America's debt limit and that there would be no agreement to avert a catastrophic default only on their terms.

In an effort to get negotiations back on track, Biden planned to call US House Speaker Kevin McCarthy, R-Calif., from Air Force One on the way back to Washington after a Group of Seven summit in Japan. World leaders at the gathering expressed concern about the dire global ramifications if the United States were to be unable to meet its financial obligations.

“It's time for Republicans to accept that there is no bipartisan deal to be made solely, solely, on their partisan terms," Biden said at a news conference before his departure. The president said he had done his part in attempting to raise the borrowing limit so the US government can keep paying its bills, by agreeing to significant cuts in spending. “Now it's time for the other side to move from their extreme position,” he said.

Biden had been scheduled to travel from Hiroshima to Papua New Guinea and Australia, but cut short his trip in light of the strained negotiations with Capitol Hill.

“My guess is he's going to want to deal directly with me in making sure we're all on the same page," Biden said about McCarthy before their expected conversation. A compromise remained within reach, the president said, despite their differences.

“I'm hoping that Speaker McCarthy is just waiting to negotiate with me when I get home," he said. “I'm waiting to find out.”

GOP lawmakers are holding tight to demands for sharp spending cuts, rejecting the alternatives proposed by the White House for reducing deficits.

McCarthy tweeted on Saturday that it was the White House that was “moving backward in negotiations.” The speaker contended that Biden would “rather be the first president in history to default on the debt than to risk upsetting the radical socialists who are calling the shots for Democrats right now.”

Republicans want work requirements on the Medicaid health care program, though the Biden administration has countered that millions of people could lose coverage.

The GOP also introduced new cuts to food aid by restricting states' ability to waive work requirements in places with high joblessness. That idea, when floated under President Donald Trump, was estimated to cause 700,000 people to lose their food benefits.

GOP lawmakers are also seeking cuts in IRS money and asking the White House to accept parts of their proposed immigration overhaul. The White House has countered by keeping defense and nondefense spending flat next year, which would save $90 billion in the 2024 budget year and $1 trillion over 10 years.

“I think that we can reach an agreement,” Biden said, though he added this about Republicans: "I can't guarantee that they wouldn't force a default by doing something outrageous.”

Republicans had also rejected White House proposals to raise revenues in order to further lower deficits. Among the proposals the GOP objects to are policies that would enable Medicare to pay less for prescription drugs and the closing of a dozen tax loopholes.

Republicans have refused to roll back the Trump-era tax breaks on corporations and wealthy households as Biden's own budget has proposed. Biden, nonetheless, insisted that “revenue is not off the table.”

For months, Biden had refused to engage in talks over the debt limit, contending that Republicans in Congress were trying to use the borrowing limit vote as leverage to extract administration concessions on other policy priorities. But with the US Treasury Department saying that it could run out of cash as soon as June 1 and Republicans putting their own legislation on the table, the White House launched talks on a budget deal that could accompany an increase in the debt limit.

The decision to set up a call with McCarthy came after another start-stop day with no outward signs of progress. Food was brought to the negotiating room at the Capitol on Saturday morning, only to be carted away hours later. Talks, though, could resume later Sunday after the Biden-McCarthy conversation.

Biden tried to assure leaders attending the meeting of the world's most powerful democracies that the United States would not default. US officials said leaders were concerned, but largely confident that Biden and American lawmakers would resolve the crisis.

The president, though, said he was ruling out the possibility of taking action on his own to avoid a default. Any such steps, including suggestions to invoke the 14th Amendment as a solution, would become tied up in the courts.

“That's a question that I think is unresolved," Biden said, adding he hopes to try to get the judiciary to weigh in on the notion for the future.