WASHINGTON, Aug 6 (Reuters) - President Donald Trump said the United States will impose a tariff of about 100% on imports of semiconductors but offered up a big exemption - it will not apply to companies that are manufacturing in the U.S. or have committed to do so.

The U.S. imports a relatively small number of chips because most of the foreign-made chips in a device — from an iPhone to a car — were already assembled into a product, or part of a product, before it landed in the country.

U.S. President Donald Trump has divulged more of his semiconductor tariff plans, but his latest threats create as many questions than answers.