Correction: A previous version of this story misquoted Rep. Mike Garcia on Ukrainian military advisers. Garcia said they are not taking the advice of U.S. military advisers.

WASHINGTON ― House Republicans’ growing opposition to a fifth Ukraine aid package means the Pentagon is unlikely to have the funding it needs to replenish U.S. weapons it has already sent to Kyiv.

Approximately $2.5 billion in Ukraine funds earmarked for the Defense Department to backfill U.S. weapons stockpiles expires at the end of the fiscal year on Saturday. And with House Republican leaders refusing to consider the Senate’s short-term budget proposal that includes $6 billion in supplemental assistance for Kyiv, it’s unlikely the Pentagon will have the replenishment funds it needs starting in October.

House Armed Services Chairman Mike Rogers, R-Ala., told Defense News there’s no backup plan to get the replenishment funds it needs for U.S. stockpiles without an additional Ukraine aid package.

“We’ve got to get the supplemental,” he said.

But that’s easier said than done.

The Senate’s Ukraine aid supplemental includes $1.5 billion in replenishment funds to backfill U.S. stocks. That’s part of a broader $6 billion package in economic and military aid for Kyiv that the Senate included in its stopgap funding bill needed to avoid a government shutdown on Sunday.

The Senate’s Ukraine aid package is significantly smaller than the $24 billion the White House asked for in August. The slimmed down package also includes $1.5 billion for the Ukraine Security Assistance Initiative, which allows the Pentagon to place contracts for defense manufacturers to build weapons systems for Kyiv over the longer-term, and another $1.5 billion in Defense Department operations and maintenance funds to help the Ukrainians ward off Russia’s invasion.

Ukrainian President Volodymyr Zelenskyy visited Capitol Hill last week, telling lawmakers his country would lose the war without continued assistance. House Speaker Kevin McCarthy, R-Calif., did not invite Zelenskyy to address the full House but met with him privately alongside the bipartisan leadership of key congressional committees.

The Pentagon says that a previous accounting error means it has approximately $6 billion in funds to keep transferring weapons to Ukraine past the end of the fiscal year. But the Pentagon will not have funds to continue backfilling those weapons without a new supplemental.

McCarthy has refused to put a Ukraine supplemental on the floor.

And the House spent a significant portion of the week holding multiple votes on whether to keep $300 million in funding for the Ukraine Security Assistance Initiative in the defense spending bill, which Republicans have repeatedly struggled to pass this month. That money does not include the funds the Pentagon needs to backfill U.S. stockpiles.

Nevertheless, the House voted 217-211 on Thursday to strip the $300 million in Ukraine Security Assistance Initiative funding from the defense spending bill and hold a separate vote on it. This vote marked an abrupt reversal from Wednesday when most lawmakers overwhelmingly voted 104-330 against an amendment from Rep. Andy Biggs, R-Ariz., that would have removed the Ukraine funds from the defense spending bill. Also on Wednesday, the House rejected another amendment from Rep. Matt Gaetz, R-Fla., to ban assistance to Ukraine in a 93-339 vote.

Despite the strong support for Ukraine, Republican leaders hope removing the assistance from the defense spending bill will appease the skeptics in their party and finally allow them to pass the legislation this week, after failing three times to do so earlier this month. The struggle to pass Ukraine aid and defense spending legislation comes as Congress threatens to shut down the government on Sunday amid the right-wing Freedom Caucus’ opposition to a short-term spending bill.

While strong bipartisan majorities continue to support Ukraine aid, previously supportive Republicans are now voting with the Freedom Caucus on the issue.

One of those previously supportive Republicans who voted against Ukraine aid this week is a defense appropriator, Rep. Mike Garcia of California. He said on Wednesday that he couldn’t support “a blank check commitment.”

“It’s not clear to me that the Ukrainians have a clearly defined win strategy to get the Russians out of eastern regions of Ukraine,” he said in a video on Wednesday. “It’s not clear to me that our nations, the United States and Ukraine, have alignment on the strategic mission objective of repelling Russia from Crimea or not. And it’s not clear to me the Ukrainians are taking the advice of American military advisers on how to win the war.”

Congress has passed a cumulative $113 billion in economic and security assistance for Ukraine since Russia’s invasion last year.

“Here again is an attempt to cut off any support for Ukraine as they fight to defend their country from an illegal Russian invasion,” Rep. Betty McCollum, the top Democratic defense appropriator, said on Wednesday. “Let’s not abandon our fellow democracies. Let’s not abandon the EU and our NATO allies now. Let’s not abandon Ukraine.”

Bryant Harris is the Congress reporter for Defense News. He has covered U.S. foreign policy, national security, international affairs and politics in Washington since 2014. He has also written for Foreign Policy, Al-Monitor, Al Jazeera English and IPS News.

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