(AP) — Top Republicans delayed a planned House vote on a short-term budget bill Tuesday to give themselves time to quell party divisions and avert a partial government shutdown by the weekend.

With conservatives insisting on commitments to curb spending, a House vote on the temporary measure planned for Wednesday will instead occur Thursday, said a GOP leadership aide. In a further signal of problems, the House Rules Committee announced it had postponed a planned meeting from Tuesday until Wednesday to work out debating rules for the budget measure.

The staffer spoke on condition of anonymity because the staffer was not authorized to speak publicly about internal party discussions.

The delay underscored the clout that conservatives wield within the House GOP as the party aims to push legislation through the House and Senate this week to keep federal agencies functioning. A partial shutdown would occur at midnight Friday night unless the Republican-led Congress approves more money, and a closure due to GOP fissures would be a jarring political blow to a party straining all year to show it can govern effectively.

The short-term legislation is designed to give bargainers more time to address remaining disputes over spending levels and other issues that have been folded into the year-end mix, including immigration and health care. Congressional leaders from both parties plan budget talks with President Donald Trump at the White House on Thursday.

Without support from their own conservatives, House GOP leaders would need backing from Democrats to push a temporary measure through the chamber. Democratic votes will definitely be crucial in the Senate, where Republicans by themselves lack the 60 votes needed to approve the legislation.

Democrats hope to use their leverage in the year-end budget battle to win concessions on spending, immigration and other issues. They have yet to say what they will do.

In further indication of the problems GOP leaders face, 34 House Republicans sent a letter to House Speaker Paul Ryan, R-Wis.., urging him to hold a vote by year’s end on extending protections for hundreds of thousands of immigrants who arrived in the U.S. illegally as children. Trump ended those protections this fall and Democrats are demanding that they be renewed in the year-end rush of business.

Earlier Tuesday, House Speaker Paul Ryan, R-Wis., declined to describe the status of internal GOP budget talks after House Republicans met privately to discuss their next steps.

“We’re having a conversation with our members about what we think the best way forward is,” he told reporters. “You’ll see when we bring the bill to the floor.”

Rep. Mark Meadows, R-N.C., head of the hard-right House Freedom Caucus, said his group was having “a good, health discussion” with leaders about ways to “fund the government without putting our military at a disadvantage.”

On Monday, the Freedom Caucus pressured GOP leaders for the short-term bill to run through Dec. 30, not Dec. 22 as has been planned.

Conservatives say setting the deadline before Christmas, when lawmakers want to go home, gives Democrats more leverage to get higher spending into the legislation.

Several Republicans said after Tuesday’s meeting that the bill would likely run through Dec. 22 but said there were no final decisions. One Freedom Caucus member, Rep. Dave Brat, R-Va., said conservatives wanted leaders’ assurances that they wouldn’t agree to unacceptably higher spending.

“It’s always the load-up-the-Christmas-tree play, go get Democrat votes, bust the budget caps,” Brat said of past spending showdowns when Democratic votes were needed.

Across the Capitol, Senate Majority Leader Mitch McConnell, said that besides temporarily financing the government, the short-term measure would make cash available to several states that are running out of money for the Children’s Health Insurance Program. That widely popular program helps provide medical care to more than 8 million children.

McConnell, R-Ky., said he was hoping that Senate Minority Leader Chuck Schumer, D-N.Y., and Democrats “will continue to work with us in good faith to pass this short-term funding bill and maintain the critical functions of the federal government.”

On Monday, McConnell expressed more confidence, saying, “We will pass it before the end of the week.”

With the budget chafing under spending caps imposed by a 2011 bipartisan budget deal, Democrats want defense and domestic programs to get equal funding increases. Both sides say they want to provide money for a health insurance program that serves more than 8 million children and for states battered by recent storms.

In addition, some from both parties want to restore billions in federal payments to health insurers that Trump halted last autumn. There are also demands for money for battling opioid abuse.