It’s Monday night in Kyiv. Here’s what you need to know.

US military and humanitarian aid for Ukraine could be at risk of being bogged down in the immigration battle brewing on Capitol Hill between Republicans and the Biden administration.

The Biden administration is expected to send another supplemental request to Congress this week for Ukraine after warning that money from the last package is nearly depleted. But, while there is broad support on Capitol Hill to give Ukraine more assistance, the path to passage is much more uncertain in the U.S. Senate.

It’s still not clear what vehicle Democrats would use to pass Ukraine aid, but one likely option would be to attach the aid to $10 billion in COVID-19 funding that is already moving through the Senate. Attaching Ukraine aid to money for COVID-19 testing and treatments, however, could put the critical wartime aid in the crosshairs of political infighting over immigration.

Where things stand on Covid relief: Before the recess, the $10 billion COVID-19 relief package stalled out after Republicans insisted they wouldn’t fast-track the process unless Democrats agreed to vote on an amendment that would block the administration’s decision to overturn Title 42, a Trump-era order that during the pandemic allowed both the Trump and Biden administrations to turn immigrants at the border back to their home countries immediately citing a public health crisis. That order is expected to be overturned at the end of May, but the decision faces stiff opposition from Republicans and some moderate Democrats who have warned the decision will cause an uptick of illegal crossings at the border.

In order to pass Covid-19 relief quickly before the recess, Republicans argued they wanted a vote to block the administration’s decision on Title 42. Senate Majority Leader Chuck Schumer wouldn’t give it to them.

Talks over how to pass both covid relief and Ukraine aid will begin Monday when lawmakers return to Washington. Schumer has also made it clear that he wants to include global vaccine funding in a Ukraine aid package. The vaccine funding wasn’t included in the $10 billion Covid package because of opposition from Republicans in the negotiations.

Why the Biden administration needs more money for Ukraine: The reason the Biden administration says it needs more money for Ukraine now is that the administration has used $2.45 billion out of the $3 billion in funding Congress authorized in Presidential Drawdown Authority funding as of April 22, according to a source familiar with the matter. Congress authorized $3 billion in that specific pot of money when they passed the omnibus spending bill in March.

Overall, Congress passed $13.6 billion in aid for Ukraine when they passed their government funding package in March. That included increasing the specific pot of money the administration had at its discretion to spend for Ukraine to $3 billion.

But the pot of money is running out. After six weeks, the Biden Administration has used up all but about $50 million of a $3 billion pot. Lawmakers are already having preliminary discussions about writing and passing another supplemental aid package for Ukraine, but conversations are still preliminary, a Congressional aide said.

Pentagon spokesman John Kirby said the administration does not want to run out of funding from the Presidential Drawdown Authority before another supplemental aid package is passed in Congress.

“We are getting close to the end of those funds, and so that’s why we are actively engaging with members of Congress,” Kirby told reporters during a briefing at the Pentagon Friday. “We don’t want to get to a point [sic] where we’re in extremes, where we’ve actually run out of the authority and the funding to execute it. So we’re having those discussions.”

Last week, the top Republican of the Senate Armed Services Committee, Sen. Jim Inhofe, called for Congress to start writing a new supplemental aid package for Ukraine in a series of tweets.