The Biden administration fears it will run out of funds for military assistance to Ukraine soon, in the event that a rumored government shutdown goes into effect, US National Security Council Strategic Communications Coordinator John Kirby said on Tuesday.

"We’ve got a little bit more funding to go, so I think we’ll be okay for the next few weeks or so. But without the supplemental request that we asked for, it [the government shutdown] will absolutely have an effect on our ability to support Ukraine well into the fall and into the winter months," Kirby told CNN in an interview.

The White House official also urged US lawmakers to allocate an additional $24 billion to Kiev at the earliest time possible to boost Ukraine's counteroffensive.

"Once we get into the winter, it gets really hard for both militaries to maneuver and to operate. So, we want to make sure we’re getting them [Ukrainians] everything they need here while they still have good conditions on the ground," he added.

Kirby stressed that a government shutdown could have a negative impact on Ukrainian forces, which are already failing to achieve the expected outcomes.

The floundering counteroffensive has prompted several members of Congress to criticize the US military aid to Kiev. The most recent defense budget has faced strong opposition for including funds intended for Ukraine.

US Republican member of Congress, Marjorie Taylor Greene, said she would vote against the Pentagon's proposed bill as long as it includes aid to Ukraine.

The Congress is required to pass a full or short-term budget before October 1, which marks the end of the current fiscal year, in order to avoid a government shutdown.

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