WASHINGTON (AP) — Environmental groups hailed a sweeping $3.5 trillion domestic spending plan announced by Democrats, saying it would make "transformational investments" in clean energy and jobs and put the nation on a path to cut greenhouse emissions by at least 50% by 2030. The plan also would move the country toward a carbon-free electric grid by 2035, with 100% of U.S. electricity powered by solar, wind, nuclear and other clean energy sources.

But with few details made public, and narrow Democratic majorities in the House and Senate, the deal reached late Tuesday was far from settled.

At least one prominent Democrat, West Virginia Sen. Joe Manchin, signaled he will oppose plans to curb subsidies for fossil fuels such as coal and natural gas. Both fuels are crucial to his rural state's economy.

"Anybody moving in a direction where they think they can walk away and not have any fossil (fuel) in play, that's just wrong," said Manchin, the chamber's most conservative Democrat and chair of the Senate Energy and Natural Resources Committee.

Eliminating fossil fuels, which are major contributors to global warming, "won't happen," Manchin told reporters Wednesday. "It can't happen and it doesn't do a darn thing but makes the world worse."

Manchin's comments were out of step with most Democrats and climate activists, who said the proposed budget deal meets President Joe Biden's climate change goals of 80% clean electricity by 2030 and a 50% cut in greenhouse gas emissions across the economy within a decade, while advancing environmental justice and American manufacturing.

The framework would fund a so-called Clean Electricity Standard that would require the electric grid to move away from fossil fuels such as coal, oil and natural gas, and replace them with renewable sources such as solar, wind and hydropower, along with nuclear energy, which currently provides about 20% of the nation's electricity.

"Given the enormity of the climate crisis, environmental injustice and economic inequality, it's critical that this agreement serve as the floor — not the ceiling — for transformational investments in clean energy, jobs and justice,'' said Tiernan Sittenfeld, senior vice president of the League of Conservation Voters.

"Any legislation on infrastructure needs to address the backlog of repairs" to roads, bridges and transit systems, as well as the challenges of climate change and racial inequities, added Deron Lovaas, a senior advocate at the Natural Resources Defense Council, another environmental group.

Sen. Tina Smith, D-Minn., called inclusion of a Clean Electricity Standard in the budget deal "the cornerstone of the progressive, practical transformation to a clean energy future we urgently need."

Sen. Jeff Merkley, D-Ore., a member of the Senate Budget Committee and one of the negotiators of the budget framework, said the plan takes "bold action" to address the climate crisis already being felt by millions in the parched West, where triple-digit temperatures have caused hundreds of deaths in recent weeks.

"We need to do even more, but this sets the stage for America to finally start working to reduce carbon pollution,'' Merkley said.

Climate activists and progressive groups have urged a Clean Electricity Standard as a central part of the Democratic-only plan, which follows a more limited, bipartisan infrastructure proposal announced last month. Many Democrats have said they will not vote for a budget package that does not include a strong electricity standard that puts the U.S. on a path to achieve goals of the Paris Climate Accord, which Biden rejoined on his first day in office.

The budget deal also sets tax incentives for clean energy and electric vehicles, authorizes a Civilian Climate Corps and spends billions on wildfire prevention and sustainable forestry.

Proposed investments in clean energy, production tax credits and other climate-related policies all "show the kind of scale and ambition that is equal to the moment,'' said Sen Brian Schatz, D-Hawaii, who leads a Democratic-only committee on climate change.

Meanwhile, the Senate Energy panel approved a Manchin-authored bill Wednesday to spend $95 billion on infrastructure, including major investments in technology to "capture" and store carbon emissions produced by coal-fired power plants. The standalone bill, approved 13-7, could be included in a bipartisan infrastructure plan being negotiated. Three Republicans — Montana's Steve Daines, Alaska's Lisa Murkowski and Louisiana's Bill Cassidy — supported the plan in committee.