The US army has used up nearly 80 percent of its interceptors for a key missile defence system, CNN reported citing several sources familiar with the matter.

According to the report, senior US military officials warned that the Pentagon’s munitions stockpile is "dangerously low," with key air defence systems particularly depleted during the war on Iran.

The US military exhausted nearly four-fifths of its THAAD missile inventory compared to pre-war figures. Meanwhile, half of its Patriot interceptors were burned through since the start of the war.

One source familiar with recent internal Pentagon reports noted that the army used "virtually all" of its highly accurate long-range, surface-to-air weapons in the same period.