Congress has been fighting over aid to the border for weeks. Trump just got in the middle of it.

Nancy Pelosi asked Trump to call off the ICE raids. She now needs to figure out a deal on humanitarian aid to the border.

The White House and Congress seem to be headed toward yet another standoff on immigration, after President Donald Trump tweeted on Saturday he would give Congress a two-week deadline to “work out a solution to the Asylum and Loophole problems.”

If Congress does not change asylum laws, Trump said he’d carry out mass deportations of immigrants in 10 US cities, a threat he has been dangling for a week. The raids were supposed to start Sunday, before House Speaker Nancy Pelosi intervened in a 12-minute phone call with the president on Friday night.

The House speaker asked the president to halt the raids during Friday’s call, a source familiar with the events told Vox. Pelosi appealed to Trump “to stop this brutal action which will tear families apart and inject terror into our communities,” a White House source told NPR.

Trump also could have been weighing another high-stakes immigration issue: ongoing bipartisan congressional negotiations for an funding bill for border aid, which the White House reportedly had been warned could hit a stonewall if the raids went forward and angered Democrats.

Whatever swayed the president, he also largely accommodated Pelosi’s requests from the call: The House speaker asked Trump to publicly tweet he would halt the planned deportations, which Trump acquiesced to, a senior Democratic aide told Vox. By Saturday afternoon, Trump tweeted he would be delaying immigration raids for two weeks “at the request of Democrats,” and wait and see if Congress could come up with a bipartisan solution on asylum.

Pelosi quickly responded with her own tweet, saying, “Mr. President, delay is welcome. Time is needed for comprehensive immigration reform.”

Pelosi has a long history of calling Trump’s bluffs in one-on-one conversations with the president, and Friday night’s call was no different. The looming question — as usual — is whether Trump will go back on his word.

Case in point: The president’s new demand for Congress on asylum law came out of the blue; Pelosi and Trump didn’t discuss asylum law on their Friday night call, the Democratic aide said.

Democrats have little incentive to wade into a new fight on asylum laws now — they and and Republicans are in the middle of their own negotiations on an immigration funding bill to address the growing crisis at the border, where holding facilities for immigrants, including teens and young children are overcrowded and filthy. But to Pelosi’s point, this is not a large comprehensive immigration bill, which would take much more time to negotiate.

As lawmakers are scrambling to address one crisis, Trump is piling on another demand about asylum that could prove to be a sticking point.

“Democrats have no interest in weakening asylum protections,” the senior Democratic aide said. “We are happy to have conversations about comprehensive immigration reform for which we have been calling.”

The next steps in Congress

While it’s unclear — and unlikely — that lawmakers would be able to finalize any large comprehensive immigration reform bill in such a tight timeframe, there is a funding package tied to humanitarian aid at the border that both chambers are set to consider this week.

This package, which is ultimately expected to allocate around $4.5 billion in additional funding for medical care, shelter and food for unaccompanied children arriving at the border, is intended to help alleviate some of the horrific conditions that currently exist.

Providing some kind of humanitarian aid to the border — a request first made by the Trump administration in May — is something that Democrats and Republicans broadly agree upon. Where they disagree, however, is on the allocation of this aid for other operational costs, like increases in detention beds, something Democrats have long opposed.

Previously, when lawmakers sought to attach this funding to a disaster aid package that passed earlier this year, Democrats were onboard with designating $3.3 billion in funding for humanitarian aid. They were not interested, though, in providing another $1.1 billion that would be used for other purposes such as detention beds and ICE personnel costs.

House and Senate lawmakers are still working through these differences this week, with the July 4 recess rapidly approaching. The House on Friday unveiled its version of the humanitarian aid package, which includes several differences from an option the Senate advanced on a bipartisan basis last week.

Notably, the House bill does not include any money for the Department of Defense, and ICE Homeland Security investigations.

That will be more than enough to sort out in the president’s two-week timeline, but there’s also some rumblings about a collaboration between Sens. Lindsey Graham (R-SC) and Dick Durbin (D-IL) on long-awaited asylum reforms.

Graham this May introduced the Secure and Protect Act, a bill that would require migrants coming from Central America to apply for asylum outside the US. He said last week that he was interested in working with Durbin to reach a bipartisan agreement on the bill, and according to CNN, the two lawmakers were holding discussions with White House aide Jared Kushner to negotiate a potential deal.

While such efforts have ultimately failed in the past, with Trump rejecting multiple bipartisan proposals that would have enshrined protections for DREAMers into law, a spokesman for Graham told Vox that the lawmakers are “still talking.”

Trump has a long history of being an unreliable negotiating partner

Congressional Democrats and Republicans have been in this situation many times before with the president: Trump makes a demand on immigration, congressional leaders negotiate with him and think they’ve struck a deal, and then Trump backtracks or comes out with a wildly different demand.

This is an administration that has been embroiled in not one, but two, government shutdowns over immigration funding. The December-January government shutdown (the longest in America’s history) was started because Trump changed his mind at the last minute and decided to not accept a government funding bill offered up by House and Senate Republicans because it didn’t have money for his border wall.

And the three-day shutdown that happened a year earlier in January 2018 stretched out because the president’s constantly shifting whims during negotiations. “I honestly don’t know what is going on,” the lead Democratic negotiator, Sen. Dick Durbin (D-IL) told Vox’s Tara Golshan in the middle of that standoff. “This president is just unable to make a promise and keep it.”

Part of the reason Democrats have had such a hard time dealing with Trump is because he often agrees with them on one-on-one phone calls or Oval Office meetings, before his staff intervenes. This has happened in talks that have had nothing to do with immigration.

Earlier this year, Democrats were optimistic they could reach a deal with Trump on an infrastructure deal after the president told Pelosi he “liked” the $2 trillion number she was proposing for a package to repair America’s roads and bridges. A month later, Trump had completely walked away from negotiations in a huff, furious over House Democrats’ investigations of him.

This is a familiar pattern: Trump says one thing, and does another. With the threat of raids hanging on his latest asylum request, House Democratic leadership has no reason to believe this time will be any different.