Ukraine has US weapons and military equipment that will last it for no more than two to three months, the Financial Times reports, citing a senior Ukrainian intelligence source.
According to the source, after this period the situation will become extremely difficult for the Ukrainian army.
"It will not be a complete collapse, but we will have to withdraw more quickly," the intelligence representative told the FT.
These forecasts are at odds with other sources who claim that Kiev has enough ammunition and weapons for at least six months.
Michael Kofman, a military analyst at the Carnegie Endowment, predicts that the impact of the shortage of armament will become apparent within a few months.
"We will start to see major consequences soon, and they will be mostly related to Ukraine's limited ability to deliver precision strikes," explains Kofman.
According to Ukrainian military analyst Pavel Narozhnyi, the most serious problem will be the shortage of HIMARS, for which Ukraine has no real substitute.
The lack of HIMARS and other precision systems will make it difficult to hit Russian military targets, which will allow Russian forces to strengthen their logistics and supply.
The Ukrainian army will retain British and French Storm Shadow/SCALP cruise missiles, but according to Narozhnyi, they are slower and easier to shoot down compared to American precision weapons.