WASHINGTON, June 29 (Xinhua) -- The U.S. Senate on Saturday narrowly advanced President Donald Trump's major tax-cut and spending bill, marking a key procedural step toward passing the legislation before the upcoming July 4 recess.

The 940-page package, formally titled the One Big Beautiful Bill Act, was approved in a 51-49 procedural vote late Saturday night, setting the stage for formal debate.

The bill aims to extend the 2017 tax cuts, cut other taxes and boost military and border security spending, while offsetting revenue losses through deep cuts to Medicaid, food stamps, renewable energy and other social welfare programs.

The vote followed hours of intense negotiations behind closed doors as Republican leaders and Vice President JD Vance attempted to unify the party's narrow Senate majority. Senator Ron Johnson of Wisconsin reversed his initial opposition and voted in favor of the bill following private discussions.

Senator Thom Tillis of North Carolina, one of two Republicans voting against the bill, cited concerns over proposed cuts to Medicaid, which would have a significant impact on his home state. Senator Rand Paul of Kentucky also opposed the legislation, criticizing its provision to raise the national debt ceiling by 5 trillion U.S. dollars.

Democrats voiced strong opposition, warning the bill would disproportionately benefit the wealthy while harming low-income Americans. Senate Democratic leader Chuck Schumer accused Republicans of rushing the process and insisted that the entire bill be read aloud on the Senate floor before debate could begin.

"If Senate Republicans won't tell the American people what's in this bill, then Democrats are going to force this chamber to read it from start to finish," said Schumer.

After the vote, senators are likely to endure overnight debate and a lengthy amendment process in the days ahead. If the bill clears the Senate, it will return to the House for a final vote before heading to the White House.

Elon Musk, former head of the Department of Government Efficiency and CEO of Tesla and SpaceX, reiterated his opposition to the bill on Saturday, writing on X that it would "destroy millions of jobs in America and cause immense strategic harm to our country."

"It gives handouts to industries of the past while severely damaging industries of the future," he added.