Congress and the Trump administration could reach agreement on full-year spending bills as soon as Thursday, according to House Appropriations Chairwoman Nita M. Lowey.

“If all goes well, we could have a deal by the end of the day tomorrow,” Lowey said Wednesday evening after reviewing an offer Republicans sent over midday. “I think their offer was real and we’re discussing it and we can find some agreement.”

Her comments represent a possible breakthrough following weeks of back and forth over hundreds of unresolved issues between the House and Senate spending bills. Lawmakers only have until a temporary spending bill expires on Dec. 20 at midnight to fund the government, or experience another partial government shutdown.

Senate Appropriations Chairman Richard C. Shelby, R-Ala., also appeared optimistic that spending bills could receive floor votes next week and said Senate Majority Leader Mitch McConnell, R-Ky., was “upbeat” Wednesday about Congress possibly passing a couple of spending packages next week.

“Our staffs are meeting right now as we talk, trying to knock off a lot of extraneous things,” Shelby said.

Negotiators are trying to narrow the scope of discussions down to just a few items before a meeting Thursday between key appropriators, Speaker Nancy Pelosi and Treasury Secretary Steven Mnuchin, Shelby said.

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Should an agreement be reached, House Democrats hope to hold floor votes as early as Tuesday, according to Lowey and Homeland Security Appropriations Subcommittee Chairwoman Lucille Roybal-Allard. In order to make that deadline, staff will likely need to work through the weekend to draft bill language and summaries, should an agreement be reached in the next day or two.

“They’ll be working all through the weekend because the hope is that we can be on the floor on Tuesday. If not, the option is a short-term [continuing resolution],” Roybal-Allard, D-Calif., told reporters Wednesday morning after members of the Congressional Hispanic Caucus met with Pelosi and Lowey to discuss the state of negotiations.

Border wall spending sought by the Trump administration, and the ability to transfer prior funds to the wall projects, is a tough sell for House Democrats. Other immigration-related matters like funding for Immigration and Customs Enforcement detention beds are also cause for concern among Democratic leaders and the rank-and-file.

Lowey said she didn’t know if the final set of spending bills would garner the full support of the Congressional Hispanic Caucus, but noted that the meeting was important to ongoing negotiations.

“I’m not sure that you’re going to get 100 percent of the caucus to support any appropriations bill,” she said. “Not everyone can vote for the bills and we just need enough votes to pass. I’d like to get the majority of Democrats and I hope we get some Republicans to support the bills because it’s always good to have bipartisan support.”

Hispanic Caucus members said the meeting covered a host of issues, including wall funding and detention bed capacity.

“We just wanted to communicate where we were and what our priorities were,” said Rep. Ruben Gallego, D-Ariz.

Officials have said Department of Homeland Security funding is unlikely to include any more than the $1.375 billion appropriated for the wall in fiscal 2019, though the administration may retain some transfer authority. 

Rep. Alexandria Ocasio-Cortez, D-N.Y., said Democratic leaders have made a “very strong commitment” on border wall funding.

“I would say funding for the wall is a sure red-line issue. It’s just completely unacceptable for the Hispanic Caucus to cast any vote for any wall funding,” she said, noting that whether Congress backfills $3.6 billion in military construction funds that was diverted to border wall construction is also a concern. “It’s not just about the upfront funding but that backdoor funding.”

Lowey and Roybal-Allard said that a Texas court ruling Tuesday blocking the Trump administration’s efforts to divert that funding was a good decision, but couldn’t say if it would throw a curve ball in the ongoing negotiations.