Congressional Republicans have paused negotiations to raise the US debt ceiling, casting doubt over talks to avoid a default.

Garret Graves, the lead Republican negotiator, left a closed-door meeting with White House representatives on Friday morning.

Mr Graves told reporters as he left that Joe Biden's administration was making "unreasonable" requests.

The White House confirmed talks have been suspended for now.

Without a deal, the US risks being unable to pay all of its bills and borrow any more money, triggering a default.

The Treasury Department has warned that, unless its borrowing limit is raised, the government will be unable to pay all of its bills after 1 June.

Failure to raise the debt ceiling from its current $31.4tn (£25.2tn) limit could see the US suspend its social insurance payments and the salaries of its federal and military employees. Default also threatens to wreak havoc on the global economy, affecting prices and mortgage rates in other countries.

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The pause is widely regarded as a negotiating ploy on Capitol Hill, but US financial markets fell on Friday in response to the news. The S&P 500 was down roughly 0.2% at 13:00 EST.

In exchange for support for raising the debt ceiling, Republicans are demanding budget cuts to the tune of $4.5tn, which includes scuppering several of Mr Biden's legislative priorities.

The White House has called the Republican proposal "a blueprint to devastate hard-working American families", although it has indicated in recent day that it may make some budgetary concessions.

But with the clock ticking, the two parties remain far apart.

"Until people are willing to have difficult conversations about how you can actually move forward and do the right thing we're not going to sit here and talk," Rep Graves said as he walked out.

House Speaker Kevin McCarthy, who was not present in the meeting, told reporters at the US Capitol: "We've got to get movement from the White House and we don't have any movement yet."

He added that the only path forward for Republicans in these talks was a commitment for the US to spend less money next year than the year before.

President Biden hopes to close a deal after he returns to the US from a G7 summit in Japan on Sunday.

"If both sides negotiate in good faith and recognise they won't get everything they want, a deal is still possible," a White House official later said