US President Donald Trump met with munitions makers at the White House as his administration pushes to expand weapons production after military operations in Iran and other conflicts drew down US stockpiles, Reuters reports.

The United States has supplied large quantities of weapons to allies while also using munitions in its own military operations, raising concerns about inventories of key air-defence and precision-guided weapons, and increasing pressure on contractors to boost output.

Two people briefed on the meeting said it ran longer than expected because everyone was given time to speak. The sources said Deputy Defense Secretary Steve Feinberg at times pushed back on industry claims about production progress, citing delays on key programmes.