US senators are working against the clock to pass a deal to raise the government's $31.4tn (£25tn) debt ceiling - and avert a debt default by the world's biggest economy.

The deal cruised through the House of Representatives by a vote of 314-117 on Wednesday, despite a few defections.

It now needs Senate approval before it can head to President Joe Biden's desk to become law.

The bill must pass by 5 June, when the US is forecast to hit its debt limit.

If the package is not approved by the deadline, a default would mean the US government could not borrow any more money or pay all of its bills. It would also threaten to wreak havoc overseas, affecting prices and mortgage rates in other countries.

With Republicans in control of the lower chamber of Congress and Democrats holding sway in the Senate and White House, a deal proved elusive for weeks until Mr Biden and House Speaker Kevin McCarthy inked a compromise last weekend.

Leaders on both sides are now keen to move the deal rapidly through the Senate.

Democratic Majority leader Chuck Schumer warned on Wednesday: "I cannot stress enough that we have no margin, no margin, for error."

Senate Republican leader Mitch McConnell told reporters that he will be "proud to support it without delay".

It remains unclear when the bill will move to a vote in the Senate.

The chamber is narrowly divided - 51 out of 100 seats are held by Democrats. With 60 votes required to approve most bills, some combination of Democratic and Republican votes will be needed.

Some Republicans have threatened to stall the bill's consideration, however, and may call for amendments if Senate leaders permit. A few have said they plan to vote against the measure.

All 100 senators need to agree to set up a final vote on the bill.

If any amendments are approved, the deal must head back to the House of Representatives for another vote - which would almost certainly push final approval past 5 June.

When the House voted on the 99-page bill on Wednesday evening, 165 Democrats joined 149 Republicans in approving it by the required simple majority.

In a statement afterwards, President Biden thanked House Speaker Kevin McCarthy, saying the Republican had negotiated in good faith.

"Neither side got everything it wanted," said the president. "That's the responsibility of governing."

The agreement suspends the debt ceiling, the spending limit set by Congress that determines how much money the government can borrow, until 1 January 2025.

The legislation will result in $1.5tn in savings over a decade, the independent Congressional Budget Office said on Tuesday.

The contents of the bill have drawn objections from both hard-line Republicans and Democrats.

"We did pretty dang good," Mr McCarthy said after the vote. But some conservative Republicans complained they had secured too few concessions in exchange for raising the debt limit.

Left-wing Senator Bernie Sanders came out against the bill on Wednesday, saying he cannot "in good conscience" support it - but he told CNN he would not delay its passage.

The last time the US came this close to overshooting its debt ceiling, in 2011, the credit agency Standard & Poor's downgraded the country's rating, a move that has yet to be reversed.