“We want to make sure that any of these countries that think they’re going to have a check to cash because of an agreement that the president may make in Paris — that they shouldn’t cash the check just yet,” Sen. John Barrasso (R-Wyo.) said of Republicans’ strategy.

Congress must pass a new spending bill by Dec. 11, when a stopgap measure expires. The simultaneous deadlines on each side of the Atlantic Ocean give Republicans a tool to derail a legacy-defining pact for the president and score a rare victory on climate policy. They also significantly raise the stakes in this year’s game of shutdown chicken.

Sen. Sheldon Whitehouse (D-R.I.) told POLITICO that he sees the dueling deadlines as a “coincidence” and notes the Paris negotiations will likely go into overtime, perhaps for as long as two days beyond Dec. 11. He also said he is “confident” that the White House will not stand for any climate-related riders in the spending bill.