U.S. House of Representatives Speaker Mike Johnson canceled a vote scheduled for Wednesday on his stopgap funding bill, saying more work is needed to build support for a measure, less than three weeks before a government shutdown deadline.

"No vote today, because we're in the consensus-building business here in Congress, with small majorities, and that's what you do," Johnson told reporters at the Capitol.

The vote had been set for later on Wednesday.

Johnson added that Republicans will be working through the weekend to find a bill that would gain enough votes for passage, now that his measure, opposed by President Joe Biden and congressional Democrats, has faltered.

House Republicans have attached a controversial provision requiring people to provide proof of citizenship to register to vote, a measure meant to force Democrats to take stances on the politically charged issue of non-citizen voting, which is already illegal in federal elections.

Republican presidential candidate Donald Trump, who continues to falsely claim his 2020 loss was the result of fraud, has urged Republicans to pass the voting measure ahead of the November 5 election.

The federal government's fiscal year ends on September 30, when funding for many agencies expires. Without some sort of extension, federal programs not deemed essential would have to suspend many of their operations, forcing thousands of government workers to go on leave.

Success for the funding bill was not guaranteed in the chamber that Republicans control by a narrow 220-211 margin. Several House Republicans have said they would vote against the measure, citing spending concerns, and many members of the caucus generally oppose stopgap spending measures.

Two Republicans joined Democrats on Tuesday in voting against a procedural move to advance the bill.

Democrats broadly see the citizenship registration requirement as meant to undermine confidence in administering elections.

"We're watching a movie we've seen over and over again," said Senate Majority Leader Chuck Schumer on Tuesday. "House Republicans are trying to pass a bill so partisan that it even splits their own caucus. This proposal isn't even serious."

The White House on Monday said Biden would veto this funding package were it to pass, citing the “unrelated cynical” voting requirement. The administration also wants a temporary funding period shorter than six months, as well as more money for the Federal Emergency Management Agency to fix infrastructure damaged by natural disasters.

Lawmakers face an even more critical self-imposed deadline on January 1, before which they must act to raise or extend the nation's debt ceiling or risk defaulting on more than $35 trillion in federal government debt.