The rapid-fire shots of tariffs and import curbs hearken back to Trump’s first term in office, when the U.S. and China engaged in a trade war that spanned most of Trump’s first four years in office and was continued to a certain extent under his successor, Joe Biden.

Existing American tariffs already restrict steel and aluminum shipments from China, which is now flooding other markets with its exports instead.

Trump spoke to reporters from the Oval Office about his decision, saying it was an “amazing day.” When asked if prices would rise as a result of the tariffs, he said that they “could go up somewhat” at first, but then “prices will also go down.”

South Korean pharmaceutical and biotechnology companies are on edge as U.S. President Donald Trump signals the introduction of tariffs on imported pharmaceuticals. Given that the U.S. is the world’s largest pharmaceutical market and S.