With Senate talks on a deal including aid to Ukraine on the brink of collapse, allies of the under-attack Eastern European nation say there is no other alternative, effective method to deliver more U.S. aid soon.

“The U.S. doesn’t get a do-over if Republicans keep blocking aid to Ukraine — those Ukrainians killed because we stopped sending them ammunition certainly won’t get a second chance,” said Doug Klain, nonresident fellow at the Atlantic Council’s Eurasia Center and policy analyst for Razom for Ukraine, an advocacy group.

Alternative pathways to delivering more cash and weapons to Ukraine’s war efforts, including using money seized from Russian governmental assets and resurrecting the lend-lease program the United States used to supply the United Kingdom before the former’s entry into World War II, could ultimately be helpful — but they simply won’t reach the country in time.

Ukraine aid got cut from a bill passed in September to temporarily keep the government open. Since then, its advocates in President Joe Biden’s administration and on Capitol Hill have been looking in vain for another “must-pass” bill to which to attach it.

The hope had been that the White House’s $100-billion-plus national security proposal, including about $60 billion in Ukraine aid, would fit the bill by linking GOP priorities on border security and aid to Israel with a Democratic one in Ukraine. (Many Democrats support aid to Israel, and many Republicans back aid to Ukraine, but each party’s base voters are more supportive of one than the other.)

Those talks are on life support, at best, amid former president Donald Trump’s work to convince Republicans to scuttle a deal to prevent a Biden political victory. Even if a bill with border provisions and Ukraine aid makes it out of the Senate, it’s unclear House Speaker Mike Johnson (R-La.), who holds a very thin majority in the House and who’s been publicly pressured by Trump to not agree to a border deal, would allow a vote on it there.

“The supplemental, we’ve got to get,” Sen. Ben Cardin (D-Md.), the chairman of the Senate Foreign Relations Committee, told HuffPost.

“We’re not giving up on the supplemental, either, to support continued aid to Ukraine,” Sen. John Cornyn (R-Texas) told reporters Wednesday. “Because I don’t believe [Russian President Vladimir] Putin will stop there.”

There are two main ideas that have been kicked around outside of the aid package: confiscating assets of the Russian government held abroad and using them to fund Ukraine; and a renewal of the World War II-era “lend-lease” program.

But both ideas have problems that would either keep them from being helpful soon, face political hurdles or hamper Ukraine’s post-war recovery.

Russian assets have largely been frozen globally since the onset of its large-scale invasion of Ukraine in February 2022. But while Russia has been unable to access them due to sanctions, they would be returned once the sanctions are lifted.

Confiscating them would go a step further, both in terms of international law and financially. Including assets held outside of the U.S., the amount available could total in the hundreds of billions of dollars. Aside from what some would see as poetic justice in using Russia’s assets against itself, the idea has bipartisan support, including from Republicans who don’t want U.S. taxpayer money to spend on Ukraine.

An asset confiscation bill, called the REPO Act, was approved by the Senate Foreign Relations Committee Wednesday on a 20 to 1 vote. A similar bill passed the House Foreign Affairs Committee in November on a 40-2 vote.

But senators and Ukraine allies say the process would take too long to be helpful soon, even if the legal objections were dealt with.

“It’ll take years for REPO to kick in,” said Cardin. “REPO’s the right thing to do, but it supplements. It does not provide the resources they need and it certainly doesn’t do it in a timely way.”

Sen. Chris Murphy (D-Conn.), one of the Democrats negotiating the deal, agreed it was not a good backup. “They need money now,” he said.

The revival of lend-lease authority, which was available up until Sept. 30 but never used, would have different problems.

“Lend-lease expired last year and would probably need to be reauthorized before it could be used,” said Klain. That would require Republicans to agree to the reauthorization.

“Even then, the U.S. would likely still need further appropriations to backfill whatever [weaponry] gets sent because the Pentagon won’t recommend weapons transfers if they deplete U.S. stocks. This isn’t a good option either.”

Unlike the aid the U.S. provided Ukraine so far, aid under lend-lease authority would be required to be repaid. Ukraine’s budget is already straining under the military costs of the war and reconstruction costs have been estimated in the hundreds of billions of dollars (which is why REPO is seen more as a way to help postwar Ukraine than an immediate solution).

Still, some senators, like Cornyn and Cardin, have spoken favorably about lend-lease.

The U.S. could just continue to send weapons from its stocks but not replace them under existing authority, Klain said, but that would be politically unpopular, would hurt military readiness and would likely be unsustainable after a while.

“Europe cannot fill the gap if the U.S. walks away. There is no substitute for American aid to Ukraine, and every day we leave the Ukrainian people out in the cold means Putin is closer to victory,” he said.

Sen. Thom Tillis (R-N.C.), one of the more outspoken Ukraine advocates in his party, warned of another consequence he would personally impose as he left a meeting on Ukraine with his colleagues Wednesday.

“People who choose to ultimately exit Ukraine, if they are successful, for as long as I am breathing, I will remind them of the consequences I am convinced we will have to live through,” he said.