Chairman of the Joint Chiefs of Staff Mark Milley stressed the U.S. military's ability to fight wars in different places if needed, but noted that it is very difficult to fight a war with Russia and China simultaneously.
During a hearing before the Senate Armed Services Committee, Milley said the U.S. military "has the ability to fight wars in many places and in different circumstances in emergency situations, but if it's a serious conflict with major powers with both China and Russia simultaneously, that's practically very difficult."
He warned that if such a scenario were to occur, the conflict would deplete huge stockpiles of ammunition, stressing that such a situation must be prepared.
Since Russian forces began the Ukraine war on February 24 last year, the Ukrainian and Russian militaries have fired huge amounts of artillery munitions, raising concerns about the quantities available to the United States after Washington supplied Kiev with large quantities of missiles.
"The big lesson from Ukraine is the massive consumption of conventional munitions, in what is effectively a limited regional war," Milley said.
"If there is a war on the Korean Peninsula, or a war of great powers between the United States and Russia, or between the United States and China, these consumption rates will be exceptional," he said.
"We have a long way to go to make sure our stocks are ready for real emergencies."
Milley's comments came a day after Army Director Gibb Camarillo said the United States was working to significantly increase its artillery production.
Washington is also increasing its production of launchers, Javelin missiles and ammunition for Himars rocket launchers, all of which have played a key role in the Ukrainian forces' push back against the Russians, Camarillo said.