WASHINGTON 

The US announced Tuesday a new $300 million "emergency" military aid package to assist Ukraine in its ongoing war with Russia. 

The Biden administration has long run out of funding from Congress to supply Kyiv's forces with armaments, and has urged lawmakers for months to provide additional funding amid Russian battlefield advances.

Amid the deadlock, the administration is funding the "modest" new package with the "unanticipated cost savings" from past contracts with arms suppliers to replace weapons in US stocks that had been sent to Ukraine, according to National Security Advisor Jake Sullivan.

"Ukraine does not have enough ammunition to fire back. That's costing terrain. It's costing lives. And it's costing us the United States and the NATO alliance strategically," Sullivan told reporters. "This ammunition will keep Ukrainians guns firing for a period, but only a short period. It is nowhere near enough to meet Ukraine's battlefield needs, and it will not prevent Ukraine from running out of ammunition in the weeks to come.”

Sullivan maintained that the package "does not displace and should not delay" Congress from quickly approving Biden's supplemental national security request, which includes $60 billion for Ukraine.

War has raged in Ukraine since Russia unilaterally invaded its eastern European neighbor in February 2021, drawing international condemnation and prompting the US and its allies to line up behind Kyiv.

Washington has since marshaled a broad coalition of nations in providing Ukraine with billions of dollars in military assistance while imposing sweeping sanctions on the Kremlin.

Ukraine's forces saw battlefield successes in a long-anticipated 2023 counter-offensive in the east, but suffered the most significant setback in months with the loss of Avdiivka in central Donetsk province in February.