The Pentagon recently warned Congress in a statement and a letter that it is running low on funds to support Ukraine and replenish U.S. military stocks. The longer that Congress waits to pass additional Ukraine funding, the more U.S. interests and military readiness will suffer.

After Congress failed to include additional funding for Ukraine in the legislation passed on Sept. 30 to avert a government shutdown, Pentagon deputy press secretary Sabrina Singh warned Tuesday that time is short to provide additional funding.

“We have enough funding authorities to meet Ukraine’s battlefield needs for just a little bit longer, but we need Congress to act to ensure there is no disruption in our support, especially as the department seeks to replenish our stocks,” Singh said.

That warning follows Under Secretary of Defense (Comptroller) Mike McCord’s letter to House leaders on Sept. 29 expressing “deep concern with the absence of security assistance for Ukraine in the continuing resolution.” McCord explained that the Pentagon “has exhausted nearly all available security assistance funding for Ukraine.” Money appropriated under the Ukraine Security Assistance Initiative, or USAI, which allows the U.S. government to procure arms for Ukraine, has run out entirely, he said.

“Without additional funding now, we would have to delay or curtail assistance to meet Ukraine’s urgent requirements, including for air defense and [155mm artillery] ammunition,” McCord warned. Timely commitments and contracting under USAI are particularly important given that Kyiv’s supply of artillery ammunition will likely already be tight in 2024, while the Russians are ramping up production. Throughout the war, relative availability of artillery ammunition has proved to be a key factor.

USAI is one of two vehicles through which Washington gives military aid to Ukraine. The other is presidential drawdown authority, whereby the administration draws directly from existing U.S. stocks, expediting delivery. The administration has around $5.4 billion left of previously appropriated PDA funding. Those funds may be enough to meet Kyiv’s immediate needs. But without more PDA funding, Washington will be hard-pressed to sustain Ukraine’s military through the winter, let alone resource another offensive in the spring.

Depending on how long Congress takes to act, delays in additional Ukraine funding could also force the United States to postpone commitments of pricier items to ensure enough budget space exists to meet Ukraine’s basic needs. Weapons on the chopping block in such a scenario could include the Army Tactical Missile System, which the White House reportedly has belatedly agreed to give Ukraine after bipartisan congressional pressure.

Even if funding ultimately arrives in time, the Hill’s dallying causes uncertainty that inhibits U.S. and Ukrainian planning. Without a sense of future U.S. aid levels, Kyiv may be forced to conserve resources to avoid the risk of being left vulnerable later. Ukraine and its Western backers also need to begin planning now for force generation and training efforts to support offensives next year.

Congress should be aware that its inaction does not only hurt Ukraine. It also hurts the U.S. military by hampering efforts to replenish U.S. stocks.

As McCord explained, the Pentagon has just $1.6 billion left of the $25.9 billion appropriated to replace U.S. military equipment and munitions sent to Ukraine through PDA. Based on this funding situation, the Defense Department has “already been forced to slow down the replenishment of our own forces to hedge against an uncertain funding future,” he warned. “Failure to replenish our military services on a timely basis could harm our military’s readiness.”

The war in Ukraine is a test of both military strength and political will. Russian President Vladimir Putin is betting that he can outlast U.S. resolve. Congressional delay in providing Ukraine with additional security assistance risks confirming Putin’s impression, extending the war and depriving U.S. troops of the weapons they need.

John Hardie is the deputy director of the Russia Program at the Foundation for Defense of Democracies think tank, where Bradley Bowman serves as the senior director of the Center on Military and Political Power.

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