President Donald Trump sent out a slew of letters Wednesday to some global trading partners, advising them of tariff levels as high as 50% for their exports to the United States.

Brazilian President Lula da Silva vowed to trigger Brazil's reciprocity law if negotiations with the U.S. fail.

Brazil’s President forcefully rebuked Trump after the U.S. leader called the prosecution of Lula’s predecessor, Bolsonaro, a “witch hunt” and hiked tariffs on the Latin American nation.