Republican lawmakers and presidential candidates are expected to put the Obama administration’s portion of a multicountry plan to slash carbon emissions through a political wringer, putting in doubt its funding and fate.

The juxtaposition on climate policy between President Barack Obama and Senate Majority Leader Mitch McConnell, R-Ky., was clear Monday. Obama warned world leaders at a climate conference near Paris they are the “last” ones who can address the “problem.” McConnell took to the Senate floor to call Obama’s plan to cut U.S. emissions unfair to middle-class Americans and “likely illegal.”

Obama administration officials are selling the pact expected to come out of Paris as a national — and global — security issue: A warming earth, with its growing seas, will leave entire countries underwater and spawn conflicts across the world.

McConnell Slams Obama’s Climate Plan as Paris Conference Begins

Such sales pitches are falling on deaf ears among Republicans, who are instead targeting Obama’s efforts. First up could be a showdown over whether to shut down the government over carbon-slashing funds.

Congressional Republicans “continue to be as difficult as humanly possible on all of this,” said John Coequyt of the Sierra Club. “It’s difficult to tell whether the majority leader is willing to provoke a standoff over the budget and shutting down the government over this.”

Pat Michaels of the CATO Institute offered a preview of one line of Republican criticism of the coming Paris pact, saying other global powers who join the U.S. atop the carbon emissions list “didn’t pledge anything real.” Citing multiple economists, Michaels said plans those countries have laid out would “be business as usual for them.”

The White House points out, though, that China has pledged join the U.S. in cutting production and assisting clean up efforts elsewhere. China and the U.S. are the world’s largest carbon emitters.

McConnell and other Republicans are making clear they will continue to fight the energy plan that is basis of the U.S. portion of the Paris carbon-reduction targets. From afar, McConnell advised the world leaders being wooed by Obama that “there is more than just an executive branch in our system of government.”

Senate Environment and Public Works Chairman James M. Inhofe, R-Okla., and 36 other Republicans are challenging billions in U.S. funds the White House has pledged for the international “Green Climate Fund.” In a recent letter, the senators criticized Obama for promising the monies “unilaterally,” saying their constituents are “worried” his promises will create jobs overseas and send their dollars into the pockets of “government officials from developing nations.”

“Congress ultimately holds the power of the purse,” the Republicans wrote Obama. “We pledge that Congress will not allow U.S. taxpayer dollars to go to the Green Climate Fund until the forthcoming international climate agreement is submitted to the Senate for its constitutional advice and consent.”

Experts say the White House is fully aware of, as McConnell put it, the “bipartisan majority in both chambers” that has previously voted against the Obama plan. That’s why the Paris pact will not be treated like a treaty, which would need Senate ratification.

Environmental groups “would like to see a final budget deal that lets the administration negotiate” with other countries before placing restrictions on the funds needed for Obama’s carbon blueprint, Coequyt said. He was referring to a massive spending bill that must be signed into law by Dec. 11 to avoid a government shutdown.

Obama has moved from “a moderate on carbon emissions to a more radical position,” Michaels said, and, “that may extract a big political cost next November.”

“If you look at the president’s clean power plan, it says we will not increase electrical generation by increasing natural gas production,” Michaels said. “That’s what’s been replacing coal generation. If he’s going to mandate so-called renewable sources, that’s going to get very expensive.

“The American people always see when their power supply is threatened,” he added. “So that means there’s probably a big debate coming during the election [cycle] about not allowing natural gas to continue replacing coal.”

Should Republicans win the White House, Obama’s plan appears doomed. A GOP president, as McConnell noted, “could simply tear it up.”

Donald Trump, the 2016 GOP presidential front-runner, on Monday called Obama’s contention that climate change is a top threat to the U.S. “one of the dumbest statements I’ve ever heard … in the history of politics as I know it.” Trump labeled Obama both “somewhat naive” and “incompetent” over his climate views and plans.

Sixty-six percent of Americans want the U.S. to enter into a global carbon emissions-slashing pact, while 27 percent oppose such a move, according to a New York Times/CBS News poll.

Related:

Obama: U.S. Helped Cause Climate Change ‘Problem’

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