Major stock indexes declined while the dollar strengthened against major currencies on Monday as President Donald Trump unveiled 25% tariffs on goods from Japan and South Korea and investors awaited further announcements in the White House's trade negotiations.

President Trump on Monday said 25% tariffs on goods from South Korea and Japan will go into effect on August 1.

The tariffs on two of America’s closest allies would go into effect Aug. 1, unless the countries reach some kind of trade agreement with the United States.