WASHINGTON — Lawmakers will reignite a debate over approving U.S. aid to Israel and Ukraine when Congress returns from Thanksgiving recess this week, with deep uncertainty underscoring the path forward amid divisions between the two parties.

Along with a defense policy bill and reauthorizing the Federal Aviation Administration by the end of the year, Congress must also grapple with a two-part deadline to fund the government that could creep up on it sooner than expected.

Under the official calendar, the House has just 12 legislative days left this year, during which top lawmakers believe they must break the logjam over foreign aid to maximize its chances of passage.

The goal is complicated by multiple factors. Republicans insist on enacting tougher U.S. border enforcement and stricter asylum laws in exchange for any Ukraine aid. And as the civilian death toll rises in the Middle East, there’s a new division among Democrats about whether or not to condition funding for Israel on its government taking active steps to stop the fighting.

“The blank check approach must end,” said Sen. Bernie Sanders, I-Vt., a leader in the progressive movement.

Senate Majority Leader Chuck Schumer told colleagues Sunday that he plans to bring Biden’s “national security supplemental package to the floor as soon as the week of December 4th.”

“The biggest holdup to the national security assistance package right now is the insistence by our Republican colleagues on partisan border policy as a condition for vital Ukraine aid. This has injected a decades old, hyper-partisan issue into overwhelmingly bipartisan priorities,” Schumer, D-N.Y., wrote in a letter. “Democrats stand ready to work on common-sense solutions to address immigration, but purely partisan hard-right demands, like those in H.R. 2, jeopardize the entire national security supplemental package.”

Biden weighs in on conditional Israel aid

Biden, meanwhile, is not drawing a hard line.

“That’s a worthwhile thought,” Biden said, referring to the idea of conditions on Israel aid, while speaking with reporters Friday about a U.S.-brokered deal to release hostages in the Israel-Hamas war. “But I don’t think if I started off with that we’d ever gotten to where we are today.”

Pressed Sunday on NBC News’ “Meet the Press,” Biden’s national security adviser, Jake Sullivan, did not say if the president prefers to slap conditions on Israel aid. “He is going to continue to focus on what is going to generate results,” Sullivan said.

Between the Democratic division on Israel, the Republican fracture over Ukraine funding and the dim prospects of an immigration deal that has eluded Congress for decades, it’s a tough puzzle to solve.

Biden “seems to care more about Ukraine’s borders than he cares about America’s borders,” Sen. Tom Cotton, R-Ark., said in an interview on “Fox News Sunday.”

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“We want to secure our border, we want to stop the flow of illegal immigrants in this country,” Cotton said. “So in return for providing additional funding for Ukraine, we have to have significant and substantial reforms to our border policy, specifically asylum and parole.”

Rep. Jake Auchincloss, D-Mass., said on “Fox News Sunday” that the GOP stance on Ukraine shows the party is “now prepared under the leadership of Donald Trump to hand Ukraine back over to Russia.”

A tight calendar and funding deadlines

Beyond foreign aid, the House has only 20 legislative days between now and the first Jan. 19 deadline to fund part of the government. Then another four days in session before the second deadline on Feb. 2 to fund the rest of it and prevent a damaging shutdown.

The pressure is on Speaker Mike Johnson, R-La., to produce the progress that hard-liners are demanding on party-line appropriations bills.

They overthrew his predecessor, Rep. Kevin McCarthy, R-Calif., for failing to move quickly enough and resorting to a short-term bill in late September. For now, they’re willing to give Johnson more time to figure it out, given that he just assumed the job one month ago.

But the hard-liners aren’t a patient bunch.

And the remaining appropriations bills will be a slog to pass. Johnson canceled votes on two of them before the Thanksgiving break, lacking enough support due to East Coast Republicans objecting to Amtrak cuts and centrists rebelling against anti-abortion language.

Other lingering GOP appropriations bills, like the one to fund the departments of Labor, Health and Human Services, and Education, also have anti-abortion provisions that make swing-district Republicans nervous. The bill to fund the Commerce and Justice departments and science policy includes provisions targeting federal law enforcement that have divided GOP lawmakers, along with conservative demands for amendments to defund former President Donald Trump’s prosecutors.

Some Republicans are backing Johnson to find a way.

“I don’t think that most Republicans blame Speaker Johnson for the problems that he is now facing, the challenges he’s facing,” Rep. Ken Buck, R-Colo., who voted to oust McCarthy as speaker, said Sunday on CBS’ “Face the Nation.” “Those were created during the McCarthy time period, and Speaker Johnson is doing a good job to work his way through those issues. So, no, I don’t think he’s going to face a rebellion.”

Buck said he favors aid to Israel and Ukraine — if they’re paid for: “We have three weeks of legislative business ahead of us, if not more, and we can get those things done and they’re very important to get done.”