The US administration has raised the global tariff rate to 15 per cent by invoking Section 122 of the Trade Act of 1974, less than a day after a Supreme Court ruling struck down its earlier authority, reported Saint Petersburg's PortNews.

The increase followed a 6-3 Supreme Court decision that said the administration exceeded its powers by using the International Emergency Economic Powers Act to impose broad levies.

An executive order signed late Friday set a 10 per cent surcharge under Section 122, which was raised to the statute's maximum of 15 per cent on Saturday. President Donald Trump said the measure was effective immediately.

Section 122 allows temporary import surcharges to address balance-of-payments deficits, capped at 15 per cent and limited to 150 days unless extended by Congress. Official documentation sets the effective date at 12:01 a.m. EST on 24 February.

Exemptions include goods qualifying under the United States-Mexico-Canada Agreement, as well as certain critical minerals, pharmaceuticals, energy products and specified electronics. Existing Section 232 duties on steel and aluminum remain in place.