Washington — Senate Majority Leader Chuck Schumer said an exchange during a White House meeting with President Biden over approving more aid for Ukraine was "one of the most intense" scenes he had ever witnessed in the Oval Office, with Speaker Mike Johnson facing bipartisan pressure to pass another round of military assistance.

The White House has urged Congress to pass a supplemental funding bill that would provide tens of billions of dollars in aid to U.S. allies and partners, including about $60 billion for Ukraine, $14.1 billion for Israel and around $9.2 billion for humanitarian assistance in Gaza. The Senate passed the legislation earlier this month on a bipartisan basis, but Johnson has so far blocked its path forward in the House.

Schumer, the president, vice president, Senate Minority Leader Mitch McConnell and House Minority Leader Hakeem Jeffries made it clear how "vital" the aid is to help Ukraine in its war with Russia, Schumer said after emerging from the meeting. He added that the issue is "so, so important" and that the group of leaders told Johnson to "get it done."

"We would, in all likelihood, lose the war" if Ukraine doesn't get more ammunition and supplies soon, Schumer said. "NATO would be fractured at best. Allies would turn away from the United States."

The New York Democrat's comments came days after he returned from leading a bipartisan delegation to Ukraine. Schumer detailed how he was "so shaken" by what he saw, and "strengthened" by the strength of President Volodymyr Zelenskyy and the Ukrainian people.

"The intensity in that room was surprising to me," Schumer said of the White House meeting, which also included discussion on the upcoming deadline to fund the government. He outlined how the leaders made clear that history is watching and urged Johnson to "do the right thing" for Ukraine.

Schumer said that Johnson "tried to answer" and made it clear he wants to address U.S. border security. For months, House Republicans have pushed for enhanced border security to accompany any additional foreign aid to Ukraine. But GOP lawmakers also widely rejected a bipartisan Senate-negotiated agreement on border security earlier this month.

"We wanted to do border and have a tough secure border plan, as we showed, we Democrats showed in the Senate," Schumer said. "He can't say he won't do Ukraine until we get border. He's tried to do border for six months and couldn't come up with a single Democratic vote."

For his part, Johnson said he was clear in the meeting that the House is exploring all avenues for supplemental funding. 

"I was very clear with the president and all those in the room that the House is actively pursuing and investigating all the various options on [the supplemental bill], and we will address that in a timely manner," he said. "But again, the first priority of the country is our border and making sure it's secure."

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.