WASHINGTON－US Senator Joe Manchin, a moderate Democrat who is key to President Joe Biden's hopes of passing a $1.75 trillion domestic investment bill, said on Sunday he would not support the package, drawing a sharp rebuke from the White House.

Manchin appeared to deal a fatal blow to Biden's signature domestic policy bill, known as Build Back Better, which aims to expand the social safety net and tackle climate change.

"I cannot vote to continue with this piece of legislation," Manchin said in an interview with the Fox News Sunday program, citing concerns about inflation. "I just can't. I have tried everything humanly possible."

He then released a statement accusing his party of pushing for an increase in the debt load that would "drastically hinder" the ability of the country to respond to the coronavirus pandemic and geopolitical threats.

"My Democratic colleagues in Washington are determined to dramatically reshape our society in a way that leaves our country even more vulnerable to the threats we face," Manchin said.

Manchin's support is vital for the bill in the 100-member Senate, where Democrats have the slimmest margin of control－the tie-breaking vote of Vice-President Kamala Harris－while the 50 Republicans are united in their opposition to the bill.

The White House responded angrily, accusing him of breaking his promise to find common ground and get the bill passed.

White House press secretary Jen Psaki said Manchin's comments "represent a sudden and inexplicable reversal in his position". Biden's administration would find a way to move forward with the legislation in 2022, she said.

US House of Representatives Speaker Nancy Pelosi said late on Sunday that lawmakers should "stay at the table to pass the Build Back Better Act". She acknowledged that "we may not have a law by the end of the year".

While describing that prospect as disappointing, Pelosi said, "we are hopeful that we will soon reach agreement so that this vital legislation can pass as soon as possible next year".

Many Democrats feel the bill is essential to the party's chances of maintaining control of Congress in next year's elections.

The White House had hoped to keep negotiations cordial and private to avoid alienating Manchin, who represents West Virginia, a state that Biden lost to former president Donald Trump by almost 40 percentage points in the 2020 election.

Uphill struggle

But many top Biden allies believe Manchin is damaging the Democratic president's political future, and Psaki's public rebuke of the senator suggested a new phase in Biden's push for legislation he regards as essential to his legacy.

Manchin's comments also drew outrage from liberal Democrats.

Senator Bernie Sanders, who helped shape the bill, called for a vote to be held on the package of measures anyway.

The bill would raise taxes on the wealthy and corporations to pay for a host of programs to thwart climate change, boost healthcare subsidies and provide free childcare.

Biden has argued that lowering such costs is critical at a time of rising inflation and as the economy recovers from the fallout of the coronavirus. Republicans say the proposed legislation would increase the federal deficit, fuel inflation and hurt the economy.

Manchin's support is crucial in a chamber where the Democrats have the slimmest margin of control and Republicans are united in their opposition to the bill.

Even if Manchin were somehow convinced to back the bill, the White House would still have to win over Senator Kyrsten Sinema, another moderate Democrat who has not committed to supporting it.

Though talks with Manchin had been going poorly, Biden's aides had expressed confidence in recent days that they would eventually secure a deal.

Agencies - China Daily