WASHINGTON — As President Joe Biden continues to urge top lawmakers to approve his $60 billion aid request for Ukraine, a grim realization has settled in for the administration that this is likely the last chance for any new US military funding to flow to the war-torn country before the 2024 presidential election.

Lawmakers have conveyed as much directly to the White House, a US official told CNN. And underscoring the current gridlock, Pentagon officials have not held a single meeting since last month to decide on what to send Ukraine from the Defense Department’s weapons stockpiles — because there is no money left to fund the aid packages.

Biden met with House and Senate lawmakers at the White House on Wednesday to outline what is at stake for Ukraine. At one point, the President turned to his national security adviser Jake Sullivan and Director of National Intelligence Avril Haines to lay out specific capabilities that Ukraine would run out of in the coming months, according to a White House official familiar with the meeting, who declined to get into more detail. Another official told CNN that they specifically pointed to air defense systems and artillery ammunition as examples of key capabilities that could be depleted without US support.

Biden also warned that US personnel were on the line, saying that if the Ukraine-Russia war spills over into NATO territory, the US would have to get directly involved in the conflict.

But House Speaker Mike Johnson, who along with other House Republicans has tied additional Ukraine funding to a broader immigration deal, said afterward that continuing to fund Ukraine risked turning it into a quagmire for the US akin to its two-decade war in Afghanistan.

“We cannot spend billions of dollars without a clear strategy articulated and I told the president in the meeting today again, as I’ve been saying repeatedly, ‘Sir, you have to articulate what the strategy is. What is the endgame?’” Johnson said Wednesday night in an interview with CNN’s Kaitlan Collins.

At the White House on Thursday, Biden told reporters he thought the meeting went well and that he believed “the vast majority of members of Congress support aid” to Ukraine.

“The question is whether or not a small minority are going to hold it up, which would be a disaster,” Biden said.

Meanwhile, inside the White House, NATO headquarters and in Kyiv, there is a keen awareness that if Donald Trump is reelected in November, he will likely slash support for Kyiv.

“The number one reason Republicans will not come out in favor of a supplemental for Ukraine is they don’t want to offend candidate Trump and his supporters,” Democratic Rep. Mike Quigley said on CNN Max on Wednesday. “He’s already made it clear what he would do — the war would be over on his first day, which means Putin gets to keep the borders he has, if not more.”

No matter what happens in American politics this year, US and Western intelligence officials believe that Russia’s war in Ukraine is likely to go on for much longer.

Assessments vary, but virtually all of them assume that there will be at least two more years of fighting, according to multiple sources familiar with the intelligence — long enough to outlast Biden’s first term. Privately, some US and Western officials say there could be as many as five more years of fighting.

Administration officials and lawmakers, including some hawkish Republicans, have for that reason been eager to approve and channel the funding to Ukraine before the clock potentially runs out at the end of 2024.

“Aside from there being a desperate need, getting as much aid in before January 2025 is on the minds of a lot of folks I’ve spoken to,” said one US official. “Not only is it important that the monies get appropriated, but that they get disbursed before the election as any FY24 funds still waiting to be spent can get blocked by Trump.”

A congressional aide familiar with the discussions said that the more hawkish lawmakers, like Republican Sen. Lindsey Graham and Republican Rep. Michael McCaul, were among those pushing last fall for Congress to approve enough funding to hold Ukrainian military forces over through the 2024 election. The administration ultimately requested $60 billion, but Congress could not reach a deal before the end of last year — doing anything more in a fraught election year may now be little more than a pipedream, the aide said.

“We are out of money,” said a US military official stationed in Europe. “The administration was able to do some magic [but] we’re getting down to the last of it.”

Said one source familiar with Western intelligence, “Basically everything depends on Biden getting reelected, doesn’t it?”

Continued Western support for Ukraine is critical, US and Western officials argue, even as the battle lines have remained largely static over the last several months following a failed Ukrainian counteroffensive to retake territory seized by Russia.

Ukrainian soldiers huddle under cover during artillery fire as the soldiers of Ukrainian Still, in the short term, US intelligence officials don’t believe a drop-off in US funding will have a major battlefield impact for Ukraine. Russia is struggling to regroup, which buys Ukraine some time, people familiar with the assessments said. But in the longer term, a lack of US aid could allow Moscow to regain momentum by ramping up its weapons supply and taking advantage of support from Iran and North Korea, one of the people said.

US officials have also considered the impact that a pullback of US support could have on other allies, particularly the message it sends about the US not having the political will to support allies and partners long term. Another concern is that Europe, which is already at the bottom of the barrel of its weapons and ammunition supplies, follows the US lead and begins to withdraw some aid.

More immediately, an end to US funding for Ukraine could limit Ukraine’s ability to conduct long-range strikes into Russian-occupied Crimea and the Black Sea —strikes that have been supported by Western weapons, including US-provided Army Tactical Missile Systems, also known as ATACMS.

If that pipeline were to dry up, US officials believe that Ukraine could lose its ability to conduct some of its most high-profile operations, a person familiar with US intelligence assessments told CNN. Ukraine’s strikes on Russia’s Black Sea fleet last fall, which forced Russia to withdraw many of its ships from Sevastopol in occupied Crimea, have been seen as a particularly effective use of the Western-provided long-range missiles.

Ukraine is expected to spend this year working to bolster its defense industrial base and rebuild its forces in anticipation of even more fighting in 2025, the US official said— a strategy that Russia is likely to focus on as well.

“That’s why continued Western support is so critical, as this next year will be when everything is done that will decide how 2025 and possibly beyond play out,” this person said.

Another attempt at a major counteroffensive by Ukraine, with the goal of splitting the Russian forces at the southern occupied city of Melitopol, is likely still at least two years away, said the US military official stationed in Europe, and US and Western officials do not expect either Ukraine or Russia to make major battlefield gains in 2024.

Both sides are “too exhausted in terms of troops and equipment to see huge moves in 2024,” this person said. The Ukrainians have discussed 2025 being “a more feasible option in terms of what they can generate to start another offensive,” the military official said.

Still, Russia has continued to try to force Ukraine into submission with huge barrages of missile and drone attacks targeting Kyiv and other major cities across the country, spreading Ukrainian air defenses thin. Ukraine is also struggling to recruit new troops, especially in the wake of a grueling attempted counteroffensive that cost thousands of lives.

Ukrainian President Volodymyr Zelensky said in a news conference last month that his military had proposed mobilizing an additional 450,000 to 500,000 men to join the war, but that he had not yet authorized the plan because it will cost Ukraine billions.

“The mobilization of an additional 450,000 to 500,000 people will cost Ukraine 500 billion hryvnia [$13 billion] and I would like to know where the money will come from,” Zelenskyy said. “Considering that it takes six Ukrainian working civilians paying taxes to pay the salary of one soldier, I would need to get 3 million more working people somewhere to be able to pay for the additional troops.”

This is not where the Biden administration hoped to be on the two-year anniversary of the conflict, with the possibility of a second Trump administration looming.

Administration and congressional officials began discussing last year how to channel as much aid to Ukraine as possible before January 2025, sources familiar with the talks told CNN.

“Not only is it important that the monies get appropriated, but that they get disbursed before the election, as any FY24 funds still waiting to be spent can get blocked by Trump,” the US official said.

At one point last fall, some more hawkish members of Congress privately estimated that Ukraine would need as much as $100 billion to get through 2024, the congressional aide said. The White House ultimately settled on a $61 billion request for 2024, around $7 billion more than it requested for Ukrainian military aid for 2023.

A congressional aide familiar with the discussions said that the longer negotiations over the supplemental drag on, the less likely it is to be approved.

“We’re in the middle of an intense election cycle, where taking a tough vote like this in the shadow of presidential and down-ballot elections is a non-starter for a lot of people,” the aide said. “So for the hawks among us, frontloading is the way to sustain support through what is going to be a politically intense year on the home front.”

Meanwhile, senior US officials have been working for the last year to come up with a legal case for seizing and transferring to Ukraine the roughly $300 billion in Russian Central Bank assets held in the West, CNN previously reported. Those assets were frozen after Russia invaded Ukraine in February 2022.

The rare maneuver would require buy-in from US allies in the Group of 7 advanced economies, as well as an act of Congress to give the president the authority to seize Russian assets held in the US. With Congress still fighting over the supplemental and how to avoid a government shutdown, it is unclear how soon that bill will come to a vote.

In the near term, Ukraine may be able to hang on, albeit in a stalemate, without US support, a Western intelligence source said. But that would still be a significant loss not only for Ukraine, but also for the US’ standing in the world, this person said.

“It shows [Russia] they were able to take territory and shows other nations they can take territory by force,” this person said. “The whole point here is to show that in today’s day and age, major powers cannot just go and take territory by force.” — CNN