Hardline conservatives are ramping up pressure on Speaker Mike Johnson to walk away from a topline spending deal struck with Senate Majority Leader Chuck Schumer, a move that threatens to derail bipartisan negotiations with Congress just days from a partial government shutdown.

GOP hardliners, who want deep funding cuts, expressed optimism after meeting with Johnson on Thursday that the speaker could revise the agreement, which would set spending at close to $1.66 trillion overall – but the Louisiana Republican was quick to say that he has made no commitment to back off the deal.

The fury from conservatives, and their effort to tank the deal, underscores the major challenge facing Johnson as he attempts to steer his extremely narrow majority ahead of a shutdown deadline next Friday. If Johnson were to walk away from the topline agreement, that would create a massive breach of trust with the Senate and could put Congress on a path to a shutdown.