The deal, first announced last week, notably lowered a threatened US tariff on Indonesian products from 32% to 19%.
Goods deemed to have been transshipped to avoid higher duties elsewhere, however, will be tariffed at 40%, a US official told reporters Tuesday.
“It is agreed that Indonesia will be Open Market to American Industrial and Tech Products, and Agricultural Goods, by eliminating 99% of their Tariff Barriers,” Trump said on his Truth Social platform.
The US leader added that “Indonesia will supply the United States with their precious Critical Minerals” and sign deals to buy Boeing aircraft and US agriculture and energy products.
The country is a key producer of minerals like copper, cobalt and nickel.
A joint statement separately released by the White House noted that, apart from the lower 19% tariff Indonesian goods will face, certain commodities not available in the United States could also be eligible for an even lower levy.
“Indonesia will remove restrictions on exports to the United States of industrial commodities, including critical minerals,” the statement added.
Meanwhile, Indonesia will drop its effort to tax the flow of data, the US official said, speaking on condition of anonymity. The official called this a “revenue grab” on US companies.
The country will also remove pre-shipment inspection or verification requirements on US goods imports, and has agreed to accept US federal motor vehicle safety standards.
Both countries are set to finalise the deal in the coming weeks, the joint statement said.
Indonesia remains among the first of a surge in deals the Trump administration promised in recent weeks, ahead of a deadline for higher tariffs to take effect on dozens of economies come Aug 1.
Washington had imposed a 10% levy on most trading partners in April and hiked duties on dozens among them – before postponing their imposition twice.
Apart from Indonesia, the US has announced pacts with Britain, Vietnam and the Philippines.
Washington and Beijing also reached an agreement to temporarily lower tit-for-tat tariffs on each other’s products, although the pause is due to expire in mid-August.
The US official said the Indonesia deal was “worth at least US$50 billion” to the US in terms of new market access and purchases that Indonesian companies intend to make.