US Senate Republicans have passed President Donald Trump's massive tax and spending bill by the narrowest margin after a turbulent overnight session.
The package would slash taxes, reduce social safety net programs and boost military and immigration enforcement spending while adding $US3.3 trillion ($5 trillion) to the country's national debt.
The so-called "big beautiful bill" now heads to the House of Representatives for possible final approval.
However, a handful of Republicans there have already voiced their opposition to some of the Senate provisions.
Mr Trump wants to sign it into law by the July 4 Independence Day holiday. House Speaker Mike Johnson said he aimed to meet that deadline.
The measure would extend Mr Trump's 2017 tax cuts, give new tax breaks for income from tips and overtime pay, and increase spending on the military and immigration enforcement.
It would also cut about $US930 billion of spending on the Medicaid health program and food aid for low-income Americans, and repeal many of former Democratic President Joe Biden's green-energy incentives.
The legislation, which has exposed Republican divides over the nation's fast-growing $US36.2 trillion debt, would raise the federal government's self-imposed debt ceiling by $US5 trillion.
Congress must raise the cap in the coming months or risk a devastating default.
Vance breaks vote tie
The Senate passed the measure in a 51-50 vote, with Vice-President JD Vance breaking a tie after three Republicans — Thom Tillis of North Carolina, Susan Collins of Maine and Rand Paul of Kentucky — joined all 47 Democrats in voting against the bill.
The vote followed an all-night debate in which Republicans grappled with the bill's price tag and its impact on the US healthcare system.
Much of the late horse trading was aimed at winning over Republican senator Lisa Murkowski of Alaska, who had signalled she would vote against the bill without significant alterations.
The final Senate bill included two provisions that helped secure her vote: one that sends more food-aid funding to Alaska and several other states, and another that provides $US50 billion to help rural hospitals cope with the sweeping cuts to Medicaid.
Following the vote, Senator Murkowski issued a statement and called it one of the hardest votes of her Senate career.
She said she voted yes despite continued reservations.
"This has been an awful process — a frantic rush to meet an artificial deadline that has tested every limit of this institution," she said.
"This bill needs more work across chambers and is not ready for the president's desk."
The vote in the House of Representatives, where Republicans hold a 220-212 majority, is likely to be close.
A White House official told reporters that Mr Trump would be "deeply involved" in pushing House Republicans to approve the bill.
"It's a great bill. There is something for everyone," Mr Trump said at an event in Florida on Tuesday.
"And I think it's going to go very nicely in the House."
The legislation has also drawn criticism from former Trump ally, billionaire Elon Musk, who has railed against the bill's enormous cost and vowed to back challengers to Republican politicians in next year's midterm elections.
House Democrats are expected to remain unanimously opposed to the bill.
ABC/Reuters