(WASHINGTON) — The House is set to vote Thursday afternoon on an aid package to Israel in what will be the first major test of Rep. Mike Johnson’s speakership.

The bill would provide $14.3 billion to Israel as it expands its military operations in Gaza following the unprecedented Hamas terror attack in early October. But it has drawn opposition from Democrats and the White House over its lack of Ukraine funding and its provision to pay for the Israel aid by slashing the Internal Revenue Service budget by the same amount.

Republican leaders projected confidence it will pass the House as they entered their closed-door conference meeting earlier Thursday.

“Israel doesn’t need a cease-fire,” Johnson said at a press conference, swiping at the calls from some Democrats for a cease-fire in Gaza. “It needs its allies to cease with the politics and deliver support now.”

“House Republicans plan to do that,” he continued. “We’re going to do it in short order and provide Israel the aid it needs to defend itself against hostages and eradicate Hamas, which is a mission that must be accomplished.”

With extremely tight margins in the House, the GOP can only afford to lose a handful of votes, as House Democratic leaders are encouraging their caucus to vote against the bill. Already, conservative hard-liners Reps. Thomas Massie and Marjorie Taylor Greene have said they won’t support the aid package.

Pressed on their opposition, Johnson said he had “great discussions” with them and he was “optimistic” about the bill’s odds.

Though if it were to pass the House, Senate Majority Leader Chuck Schumer said the Senate will not take up the bill.

“The Senate will not be considering this deeply flawed proposal from the House GOP and instead we will work together on our own bipartisan emergency aid package that includes aid to Israel, Ukraine, competition with the Chinese government and humanitarian aid for Gaza — so much needed,” Schumer said in remarks on the Senate floor on Thursday morning.

The White House also already threatened President Joe Biden would veto the package if it landed on his desk.

“This bill would break with the normal, bipartisan approach to providing emergency national security assistance by conditioning funding on offsets, politicizing aid to Israel, and treating Israel differently from our other allies and partners. And that new and damaging precedent would have devastating implications for our safety and alliances in the years ahead,” the Office of Management and Budget wrote in a lengthy statement on Wednesday.

Johnson said Israel aid needs to be handled in a “responsible manner,” pointing to the exploding national debt.

Rep. Jim McGovern, D-Mass., specifically took aim at Republicans cutting IRS funding as part of the package — a move the Congressional Budget Office said would add $12.5 billion to the deficit in the next decade.

“The way you are handling legislation today is an international embarrassment for our country,” McGovern said of Republicans in a speech on the House floor.

Asked by ABC News Senior Congressional Correspondent Rachel Scott if he would consider putting an Israel aid package on the floor that doesn’t include such spending cuts, Johnson said no.

“We have obligations and we have commitments and we want to protect and help and assist our friend, Israel, but we have to keep our own house in order as well,” he said.

Johnson later told reporters, “If Democrats in the Senate or the House or anywhere else wants to argue that hiring more IRS agents is more important than standing with Israel in this moment, I’m ready to have that debate.”

Johnson said Ukraine aid would come next, though a growing number of House Republicans have expressed opposition to supplying the war-torn nation with more funding as it continues to stave off Russia’s invasion. Johnson said House Republicans will pair it with border security provisions to try to get it across the finish line.

The House is scheduled to vote on the bill closer to 5:30 p.m. Thursday.

ABC’s Allison Pecorin contributed to this report.

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