A shipping loophole exempting small-value packages from tariffs ended at 12:01 a.m. Friday, meaning that packages shipped into the U.S. under $800 are now subject to additional taxes.

Earlier this year, President Donald Trump ended the loophole for small-value packages shipped from China and Hong Kong.

Senior White House officials hailed the move in a call with reporters Thursday, saying that it was a crucial step in Trump’s efforts to rebalance trade and also will help crack down on the importation of illegal goods, including fentanyl.