WASHINGTON — Ukrainian President Volodymyr Zelenskyy kicked off a quick visit to Washington on Monday, warning in a speech at a defense university that Russia may be fighting in Ukraine but its “real target is freedom” in America and around the world. He also issued a personal plea for Congress to break its deadlock and approve continued support for Ukraine.

His time in Washington, which will include meetings Tuesday at the White House and with Congress, is part of a last-minute push by the Biden administration to persuade lawmakers to pass a supplemental funding bill, as officials warn that the money for Ukraine is running out. But the mood on Capitol Hill ahead of Zelenskyy’s visit was grim as leading Senate negotiators said they were essentially out of time to strike a deal on U.S.-Mexico border security policies that Republicans have insisted be included in the package.

President Joe Biden has asked Congress for $61.4 billion for wartime funding for Ukraine as part of a $110 billion package that also includes money for Israel and other national security priorities. But the request is caught up in a debate over U.S. immigration policy and border security. The U.S. has already provided Ukraine $111 billion for its fight against Russia’s 2022 invasion.

“If there’s anyone inspired by unresolved issues on Capitol Hill, it’s just (Russian President Vladimir) Putin and his sick clique,” Zelenskyy told an audience of military leaders and students at the National Defense University. “Ukrainians haven’t given up and won’t give up. We know what to do. And you can count on Ukraine. And we hope just as much to be able to count on you.”

Defense Secretary Lloyd Austin, who introduced the Ukrainian president, said America’s commitment to Ukraine is unshakeable and supporting the war is critical to ensuring the security of the U.S. and its allies.

“America’s commitments must be honored. America’s security must be defended. And America’s word must be kept,” Austin said.

He said Zelenskyy is “living proof that a single person’s leadership can help rally an embattled democracy and inspire the free world and change the course of history.”

With Congress in its final week before leaving for the holidays, questions remain as to whether Republicans will be able to come to an agreement on any rounds of future funding for Ukraine or Israel without White House concessions on border security as illegal crossings surge. But any border package also runs the risk of alienating some Democrats.

Sen. James Lankford, an Oklahoma Republican who is leading the GOP negotiations, said large disagreements remain in the negotiations and predicted there would be no breakthrough by the end of the week.

Lankford said in recent days he was left out of talks between Senate Democrats and the White House, adding, “It was just a frustrating weekend.”

Sen. Chris Murphy, D-Conn., who is involved in the talks, said he hoped Zelenskyy’s visit would encourage Republicans to compromise from their policy demands. He acknowledged that Congress approving the funding this year “seems like an uphill climb, but not impossible.”

This is Zelenskyy’s third visit to Washington since the war began, and he appeared at NDU wearing his trademark Army green long-sleeve shirt — emblazoned with “I’M UKRAINIAN.” His lobbying task, however, has gotten increasingly difficult, from the hero’s welcome he received in the Capitol last year to the bitterly divided Congress this year.

He noted that 82 years ago on this day the U.S. went to combat in Europe, as then-President Franklin D. Roosevelt signed the declaration of war against Germany. Now, he said, though the U.S. has no troops on the ground in Ukraine, it is supplying critically needed weapons and equipment.

“Every one of you here understands what it means for a soldier to wait for ammunition, waiting for weeks, months without knowing if support will come at all,” he told the university audience. “When the free world hesitates, that’s when dictatorships celebrate.”

Zelenskyy also met Monday with Kristalina Georgieva, managing director of the International Monetary Fund. In a statement, Georgieva said “timely and predictable” financing for Ukraine is critical to sustaining the country’s economic gains and its plans to implement financial reforms and maintain financial stability.

According to the Defense Department, there is about $4.8 billion remaining in presidential drawdown authority, which pulls weapons from existing U.S. stockpiles and sends them quickly to the war front, and about $1.1 billion left in funding to replenish the U.S. military stockpiles.

John Kirby, the White House National Security Council spokesman, told reporters Monday that Zelenskyy’s visit comes at a critical time.

“This is exactly the right time to be having President Zelenskyy in town to have these discussions, because of what’s going on in Ukraine, the increased activity we’re seeing by the Russian armed forces as winter approaches, but also what’s going on on Capitol Hill,” said Kirby.

He said Biden will make clear to Zelenskyy when they meet that the White House is standing firm on the supplemental budget request. White House spokesman Andrew Bates said top Office of Management and Budget, National Security Council and White House legislative affairs officials have continued to press the case for the funding.