By Jeff Mason, Bart H. Meijer and David Brunnstrom WASHINGTON/BRUSSELS (Reuters) -U.S. President Donald Trump opened a new phase on Monday in the trade war he launched this year, telling partners, from powerhouse suppliers such as Japan and South Korea to minor players,

President Trump said Japan and South Korea would face tariffs of 25 percent unless they reached an agreement with the United States. Other countries received notice of higher levies.

Donald Trump has said he will impose 25 per cent tariffs on imports of goods from Japan and South Korea, in an announcement that sent US stocks sliding. The president on Monday said the new levies on both countries would come into effect on August 1. Trump has vowed to announce tariff rates for dozens of other trading partners in coming days.