Congress returns this week in hopes of quickly completing the year’s remaining work, but the dash to the finish could create headaches in the early part of Donald Trump’s presidency, particularly when it comes to the debate over government spending.

Lawmakers are expected to spend the coming week working to pass a short-term spending bill, the annual defense policy measure and a sweeping biomedical research and drug approval package. They also hope to wrap up work on a water infrastructure bill that includes money to help address the water crisis in Flint, Mich.

Republican leaders are eager to wrap up their work and head home for the year, but many of the bills on the agenda have the potential to force the GOP to renegotiate policies within a few months when a new Congress and president are in office.

Perhaps the biggest issue for Republicans early next year will be deciding a spending plan for 2017. House and Senate leaders are negotiating the final details of a stopgap spending bill to keep the government open past the current Dec. 9 deadline. There is no real question that Congress will avert a government shutdown, but leaders are still debating how long into next year it should keep the government funded so that the new Congress and Trump can hammer out a final spending deal for the 2017 fiscal year, which began Oct. 1.

House leaders announced before Thanksgiving that Trump and his team had asked Congress to prepare a spending bill that would keep the government open at current spending levels through the end of March. That measure would allow Trump to quickly put his own stamp on government spending. But Senate leaders worried that it would be difficult early next year to write a new spending bill while simultaneously working to vet and approve Trump’s Cabinet appointments and some of the party’s top legislative priorities.

House Speaker Paul D. Ryan (R-Wis.) told reporters Thursday that he and other House leaders took those concerns into account and are working on drafting a spending bill that would go beyond March.

“We’re working with Leader McConnell on their calendar to make sure that we can accommodate some of their, you know, concerns, which I think are legitimate because they have different responsibilities than the House does,” Ryan said.

Ryan refused to specify just how long the spending bill would last, but many lawmakers with knowledge of the talks guessed it would go until the end of April or May. While that may give Trump a greater cushion, it could also lead to an ugly spending fight in the spring.

Senate Democrats next year could seek to block a spending package if it provides less funding for programs they support, and House conservatives could balk if they feel the overall funding number is too big. Both scenarios could be a headache for the new Trump administration.

The possibility of such a fight has some in the GOP warning it’s a mistake to kick this year’s spending decisions into the next administration.

“This is bad for the military; it’s bad for every agency of the government,” Rep. Tom Cole (R-Okla.) said of the short-term bill. “I think it’s a bad decision, and I think all concerned will live to regret it.”

Still, the stopgap spending bill is expected to be cleared this week, and much of the focus now is on efforts to persuade leaders to add special provisions to the legislation. One of the more controversial items is a policy rider backed by the Obama administration that would allow the embattled Export-Import Bank to operate at full capacity for the first time in more than a year. Some Republicans in Congress have refused to approve new members to fill three open positions on the agency’s five-member board of directors.

The bank provides financing for American companies looking to conduct business overseas, and some conservatives deride its mission as “crony capitalism.” It cannot vote to allow new loans worth more than $10 million unless at least one of the open positions is filled. Democrats are working with some friendly Republicans to drop the measure that requires a three-member quorum, a move that conservatives strongly oppose.

“I think if they get included, it would be a major debate,” Rep. Mark Meadows (R-N.C.) told reporters Thursday.

If the Export-Import rules are changed, Trump can expect in the spring to relitigate the fight over the bank while also attempting to hash out spending priorities — essentially repeating the same battles that plague lawmakers today.

Leaders also hope to finish work on the Water Resources Development Act, an environment and water infrastructure bill that includes aid for the Flint water crisis and a controversial “Buy American” provision.

The House and Senate passed separate versions of water projects legislation earlier this year, and negotiators are working to hammer out any final differences, including whether the bill will include a measure to require the government to purchase American-made steel for any upcoming infrastructure projects.

Some Republicans want funding for the “Buy American” language stripped from the bill, putting them directly at odds with Trump, who backed the concept at a rally in last week.

“Whether it’s producing steel, building cars or curing disease, we want the next generation of innovation and production to happen right here in America and right here in Ohio, right?” Trump said Thursday in Cincinnati.

The Senate is also set to vote on the only bill expected to remain relatively untouched by a future Trump administration. The 21st Century Cures bill, which passed the House last week, aims to streamline the approval of new drugs, improve mental health care and provide money for medical research, including $1.8 billion for Vice President Biden’s cancer moonshot initiative. The legislation has faced some opposition on the left, but it is expected to easily be approved early this week.

In the realm of foreign policy and defense, the main question before Congress is whether lawmakers later this month will have to override a pair of potential presidential vetoes.

The Senate is expected to pass the $618.7 billion annual defense policy bill this week. The House passed the measure on Friday by a vote of 375 to 34. But the White House has not yet indicated whether the president would sign the bill.

While the legislation steered clear of several policy changes the Obama administration opposes, it did not fully resolve a dispute over spending. The bill relies on an extra $3.2 billion in war funds, which is more than lawmakers agreed to in a two-year budget deal struck last year, to pay for Pentagon programs and military operations.

War funds are not subject to budget caps and can be used as a way to provide extra money for the Pentagon without running up against the spending restrictions known as sequestration. But the White House has strongly resisted such budgeting moves. Last year, Obama vetoed Congress’s first attempt to pass a defense policy bill due to his opposition to how Congress was tapping the war-funding account.

Obama is also sitting on a House- and Senate-approved bill to extend the Iran Sanctions Act for 10 years — legislation that lawmakers believe is vital to maintain the threat that the United States will retaliate against Iran if it violates the terms of a nuclear deal struck last year.

Iran’s supreme leader, Ayatollah Ali Khamenei, has warned that the sanctions extension would violate the United States’ obligation under the nuclear pact and is urging Obama to veto the bill. The Obama administration has resisted efforts to pass the extension, arguing that the president already has ample authority to punish Iran for violations of the nuclear pact and other aggressive moves, such as a recent spate of ballistic missile launches.

Mike DeBonis contributed to this report.