President Donald Trump’s sweeping tariffs took effect Wednesday over the concerns of many of the nation’s billionaires, as even longtime supporters of the president—including Elon Musk—have expressed concern about the tariffs and their impact on the economy.

A pair of Donald Trump's top advisers are at odds. Elon Musk called Peter Navarro a "moron" and "dumber than a sack of bricks."

Tech-billionaire and Tesla CEO Elon Musk made direct yet unsuccessful appeals to U.S. President Donald Trump to reverse tariffs over the past weekend, Washington Post reported on Monday citing two people familiar with the matter.