US President Donald Trump invoked the Defence Production Act in an effort to bolster delivery of weapons whose stockpiles critics say have been strained by the war in Iran and other conflicts.

The president cited “systemic constraints in the munitions industrial base” in his order for Defence Secretary Pete Hegseth to make “voluntary agreements and plans of action” to address the depleted US defence capacity, according to a memo dated June 11 and posted in the Federal Register.

It was not immediately clear what those agreements might entail that would go beyond the administration’s engagement with defence contractors like Lockheed Martin Corp and RTX Corp.

The 15-week Iran conflict has spurred concerns that the US has stretched its resources, drawing down stockpiles of critical munitions.

Trump administration officials have emphasised a need to limit resources to allies and partners, such as war-torn Ukraine, as part of a drive to prioritise the domestic industrial base.

At the same time, Hegseth has pushed back on worries over US stockpiles, saying last month that “the munitions issue has been foolishly and unhelpfully overstated” and that “we have plenty of what we need”.