Conservatives thrust the House back into chaos on Wednesday, grinding business to a halt in protest of the spending deal Speaker Mike Johnson struck with Democrats to avert a government shutdown and leaving the funding package in limbo.

A dozen hard-line Republicans defected from the party line to tank a routine procedural measure, blocking consideration of a pair of G.O.P. bills in what amounted to a warning shot by members of the ultraconservative Freedom Caucus that they would not stand for the agreement. As the measure failed, members of the group could be seen in animated discussion with Mr. Johnson and his deputies on the House floor.

The Republican revolt underscored Mr. Johnson’s predicament in trying to steer the spending deal through the closely divided House, where it has enraged a sizable bloc of Republicans, while keeping his grip on his job. The upheaval came as it was becoming clear that Congress would most likely have to resort to yet another short-term spending patch — something Mr. Johnson had previously ruled out — to buy time to push a bipartisan deal to fund the government.

The scene on the House floor on Wednesday was a procedural protest that was once seen as all but unthinkable in the chamber, but which right-wing lawmakers used repeatedly last year against former Speaker Kevin McCarthy to protest his spending deals before they eventually deposed him.