Postal carriers across Europe are planning to suspend some shipments to the U.S. as the nations prepare for the end of a longstanding trade rule.

Certain shipments from Germany, Spain, France, Belgium, Sweden, Denmark, Finland, Norway and Switzerland are due to be paused in the coming days and weeks after President Donald Trump signed an executive order ending the century-old “de minimis” exemption.

The trade policy, sometimes referred to as a “loophole,” has allowed shipments valued under $800 to enter the U.S. virtually duty-free. The practice is set to end for imports from around the globe on Friday following Trump’s executive order.

The de minimis exemption for goods coming from China and Hong Kong, which have long accounted for the bulk of those shipments, ended in May.

The suspensions will impact shipments valued under $800, and largely exclude gifts and letters. Most of the countries said they have to pause shipments because their systems weren’t built for the new requirements and they’re unsure how to properly process the shipments under the new rules.