Washington - U.S. Senate Democrats, over uniform Republican opposition, on Sunday approved sweeping legislation to combat climate change, trim health care costs and raise taxes on highly profitable corporations.

The measure, a scaled-down version of President Joe Biden's long-stalled economic legislative plan, calls for the biggest U.S. investment ever in attacking the effects of global warming, $370 billion to boost the use of clean energy, encourage Americans to buy electric vehicles and reduce plant-warming emissions 40% by 2030.

The legislation will also for the first time authorize the U.S. government to negotiate the cost of some drugs with pharmaceutical companies to potentially lower the cost of medicines for older Americans, extend health insurance subsidies for millions of people and impose a 15% minimum tax on billion-dollar companies that now pay nothing. The bill would also add 87,000 more federal tax agents to further scrutinize individual and corporate tax returns to catch tax cheaters and cut the chronic U.S. budget debt by about $300 billion.

The measure narrowly survived a key test vote Saturday by a 51-50 margin, with Vice President Kamala Harris casting the tie-breaking vote after all 50 Senate Democrats supported the legislation and the 50-member Republican caucus uniformly opposed it.

Democrats engaged in months of rancorous debate over what was originally a $2 trillion measure, what Biden called his Build Back Better plan. Now, with U.S. consumers worried about the sharpest increase in consumer prices in four decades - a 9.1% annualized surge in June - Democrats are calling the legislation the Inflation Reduction Act.

However, the non-partisan Congressional Budget Office review of the legislation said the bill's provisions would have a "negligible effect" on inflation during the remainder of 2022 and little effect next year either.

The entirety of the legislation appeared doomed until Senate Democratic Majority Leader Chuck Schumer, with Biden's approval, was recently able to reach agreement with two centrist Democrats, Senators Joe Manchin of West Virginia and Kyrsten Sinema of Arizona, on tax and climate control provisions in the proposal that they would accept.

As debate opened Saturday, before lawmakers from both parties offered an array of amendments that were rejected, Schumer said, "This historic bill will reduce inflation, lower costs, fight climate change, and it's time to move this nation forward."

Senate debate on the measure was continuing Sunday but Democrats approved the legislation later in the day, on the same 51-50 party-line margin requiring Harris to cast the tie-breaking vote as she did on the opening vote to begin debate. The House of Representatives is expected to pass it Friday and send it to the White House for Biden's signature.

The debate also played out on Sunday television talk shows.

Democratic Senator Richard Blumenthal of Connecticut, who supports the legislation, told CNN's "State of the Union" show that its passage would give the tax-collecting Internal Revenue Service agency the greatly expanded staff it needs to "go after" tax cheats and "the biggest earners."

He also noted that Americans "overwhelmingly want to cut the cost of their medicine," a provision that could be achieved for some drugs prescribed for older Americans under the country's Medicare health insurance program.

But Republican Senator Lindsay Graham of South Carolina balked at Blumenthal's analysis of the measure, saying that tax agents are "going after Uber drivers and nurses. They're going after everyone."

He said the legislation is "going to make everything worse. It's not going to help [cut] inflation."