WASHINGTON, DC - DECEMBER 06: U.S. President Joe Biden delivers a statement urging Congress to pass his national security supplemental from the Roosevelt Room at the White House on December 06, 2023 in Washington, DC. Following a virtual meeting with G7 leaders and Ukrainian President Volodymyr Zelensky, Biden called on Congress to take action on the security budget supplemental request which includes funding to support Israel, Ukraine and added security along the U.S.-Mexico border. (Photo by Anna Moneymaker/Getty Images)
Washington CNN  — 

President Joe Biden on Wednesday urged Congress to resolve negotiations over the future of Ukraine funding, saying “petty partisan politics can’t get in the way” of aid for Kyiv.

“History’s going to judge harshly those who turn their back on freedom’s cause,” the president said. “We can’t let Putin win.”

The speech, which was not originally on the president’s daily schedule, served as an effort to jumpstart stalled negotiations over the administration’s proposed $106 billion aid package, and comes at a critical time for Ukraine as the White House has warned that aid for the war-torn country is running out.

The package includes about $60 billion in aid toward Ukraine’s defenses against Russia, with the rest going toward Israel’s war with Hamas, security in Taiwan and funding for operations at the US-Mexico border. Top Republicans, weary of adding more to the $111 billion the US has already sent to Ukraine, have asked that any further funding be tied to major immigration-related policy changes.

Biden said he was willing to make “significant compromises on the border,” conceding the country’s immigration system is “broken,” but added Ukraine’s needs are too critical to wait. He called out “extreme Republicans” as negotiators remain at a critical impasse over the sticking point issue of border security, saying those Republicans are “playing chicken with our national security.”

“Frankly, I think it’s stunning we got to this point in the first place,” Biden said. “… Russian forces are committing war crimes – it’s as simple as that. It’s stunning.”

“Who is prepared to walk away from holding Putin accountable for his behaviors?” the president asked. “I’ll tell you I’m not prepared to walk away, and I don’t think the American people are either.” Failure to pass the funding, Biden warned, would give Putin “the greatest gift he could ask for.”

He again warned that Putin would “keep going” if he takes Ukraine, suggesting that Russia could eventually attack a NATO ally and draw US troops into conflict.

Negotiations in Congress over the aid package have gotten tense, with a classified briefing on Ukraine on Tuesday devolving into a shouting match between senators arguing about the border.

The White House telegraphed to Senate negotiators last week the border policy changes that they were open to tying to the Ukraine-Israel aid package –including some changes reminiscent of the Trump-era that previously received fierce pushback from advocates, according to three sources familiar with the discussions.

Sources tell CNN the changes the White House telegraphed to the hill included, for example, raising the credible fear standard for migrants seeking asylum, which could have the effect of making fewer migrants eligible for asylum.

They also were open to casting a wider net of undocumented immigrants subject to the fast-track deportation procedure known as “expedited removal,” which the Trump administration tried to do and would give greater latitude in quickly deporting undocumented immigrants.

The White House’s involvement in the talks has been a delicate balance as publicly the administration has tried to let lawmakers work out their negotiation. But with time running short and the stakes high for what a failed supplemental could mean for Ukraine on the battlefield, pressure is growing for Biden to more directly engage. CNN reached out to the White House for comment.

Earlier Wednesday morning, the president met virtually with G7 leaders and Ukraine President Volodymyr Zelensky, who made an urgent plea to members of the US Congress for additional aid.

After that meeting, the administration announced a new Presidential Drawdown Authority (PDA) package for security aid to Ukraine valued at $175 million. The State Department said in a release that barring additional funding from Congress, the package would be “one of the last” provided.

The package includes ammunition for High Mobility Artillery Rocket Systems (HIMARS), 155mm artillery rounds, Javelin anti-armor missiles, High-speed Anti-Radiation Missiles, demolition munitions for obstacle clearing, small arms and equipment spare parts. The package is slightly larger than the last couple of PDAs announced this year, though markedly smaller than the majority of packages announced since Russia’s invasion as available resources begin to run low in the absence of new funding from Congress.

The Senate is expected to hold a vote later Wednesday toward advancing that aid package, which the White House “strongly supports,” but Republicans appear poised to block the move.

This story has been updated with additional reporting.