Mr. Trump is also threatening tariff hikes for Mexico and China, but the U.S.' southern neighbor got a 90-day extension on Thursday, and an Aug. 12 deadline to strike a deal with China is expected to be extended for three months, too.

U.S. President Donald Trump signed an executive order Thursday modifying his so-called reciprocal tariff rates for certain countries, including the authorization of a 15 percent rate for Japan. Trump's signing came just hours before the expiration of his monthslong pause on country-specific tariffs,