US President Donald Trump has invoked the Defense Production Act to address constraints in weapons supply and development for munitions production and supply chains, according to a memo made public on Tuesday.

"I hereby find that conditions exist which may pose a direct threat to the national defense or its preparedness programs," Trump said in a June 11 memorandum to US Secretary of Defense Pete Hegseth.

He cited "limited production capacity, fragile supply chains, long-lead dependencies, and related production bottlenecks."

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