The Pentagon has become concerned about the shortage in stockpiles of artillery shells, as well as air defense and anti-tank missiles to Ukraine.
CNN reported Thursday that the US was running low on weapons and ammunition.
Three US officials with direct knowledge of the matter told CNN that the US was running low on some high-end weapons systems and ammunition available to transfer to Kiev regime.
Among the weapons systems where there’s particular concern about US stockpiles meeting Ukrainian demands are 155mm artillery ammunition and Stinger anti-aircraft shoulder-fired missiles, the sources told CNN.
Meanwhile, US Defense officials say the shortage was not affecting US military forces, as the weapons sent to the Ukraine conflict were not the same as what the US forces keep for their own military's use.
Earlier reports revealed that the United States was sending old missiles that its own military had stopped using to Ukraine.
In the meantime, the US is trying to ramp up the production of certain types of arms.
Since the start of Russia’s military operation in Ukraine in late February, the US and its Western allies have been providing Kiev with billions of dollars in weapons and ammunition, with Moscow repeatedly warning that weapons shipments will only prolong the conflict.
The Kremlin's spokesman Dmitry Peskov said last month that the continuation of US weapon supplies to Ukraine "will only drag the conflict out and make it more painful for the Ukrainian side, but it will not change our goals and the end result."
According to the Pentagon, as of early November, Washington has committed to sending Kiev over 1,400 Stingers, 8,500 Javelins, 142 155mm Howitzers, and up to 903,000 155mm artillery rounds.
The US has supplied the Kiev regime with more than $16.8 billion worth of weapons and ammunition since Russia launched its military campaign against Ukraine on February 24.
The United States and its allies now want to restock the weapons they shipped to Ukraine in the past months.
In this regard, US weapons manufacturer giant Raytheon has been closing new contracts with the military to boost its arms production.
President of Raytheon Missiles & Defense, Wes Kremer, said earlier this year that the orders placed by the US military will help them "fulfill our current foreign military sale order."