Trump signed a presidential proclamation laying out his argument that timber, lumber and furniture imports are eroding US national security to justify the new duties under Section 232 of the Trade Act of 1974.

The proclamation said the tariff rates would start on Oct 14 but added that duties will increase on Jan 1 to 30% for upholstered wooden products and to 50% for kitchen cabinets and vanities imported from countries that fail to reach an agreement with the US.

The action is the first in three sectors that Trump said last week would get steep new duties as early as Oct 1, including patented pharmaceutical imports and heavy truck imports.

But Monday’s proclamation sets the start of the lumber and furniture duties two weeks later, at 12.01am EDT (0401 GMT) on Oct 14.

Trump’s proclamation said wood product imports are weakening the US economy, resulting in the persistent threats of closures of wood mills and disruptions of wood product supply chains and diminishing utilisation of the US domestic wood industry.

“Because of the state of the US wood industry, the US may be unable to meet demands for wood products that are crucial to national defence and critical infrastructure,” the statement said.

The order added that wood products are used for “building infrastructure for operational testing, housing and storage for personnel and materiel, transporting munitions, as an ingredient in munitions, and as a component in missile-defence systems and thermal-protection systems for nuclear-reentry vehicles.”