Washington: US President Donald Trump on Thursday secured a major political victory when Congress narrowly passed his flagship tax and spending bill, cementing his radical second-term agenda and boosting funds for his anti-immigration drive.

The bill underlined the President's dominance over the Republican Party, which had been wracked by misgivings over a text that will balloon the national debt and gut health and welfare support. A small group of opponents in the party finally fell into line after Speaker Mike Johnson worked through the night to corral dissenters in the House of Representatives behind the "One Big Beautiful Bill." The bill squeezed past a final vote 218-214, meaning it can be on Mr. Trump's desk to be signed into law on the July 4th Independence Day holiday.

"One of the most consequential Bills ever. The USA is the 'HOTTEST' Country in the World, by far!!!" Trump said on social media as he scented victory. The timing of the vote slipped back as Democratic minority leader Hakeem Jeffries spoke against the bill for nearly nine hours to delay proceedings. The legislative win is the latest in a series of successes for Trump, including a Supreme Court ruling last week that curbed lone judges from blocking his policies, and US air strikes that led to a ceasefire between Israel and Iran.

His sprawling mega-bill just passed the Senate on Tuesday and had to return to the lower chamber for a rubber stamp of the senators' revisions.

The package honours many of Trump's campaign promises: boosting military spending, funding a mass migrant deportation drive and committing $4.5 trillion to extend his first-term tax relief.

"Today we are laying a key cornerstone of America's new Golden Age," Johnston said. But it is expected to pile an extra $3.4 trillion over a decade onto the country's fast-growing deficits, while shrinking the federal food assistance program and forcing through the largest cuts to the Medicaid health insurance scheme for low-income Americans since its 1960s launch.