The US Postal Service has suspending inbound international packages from China and Hong Kong Posts, delaying or blocking shipments from giant online retailers, and Amazon competitors, like Shein and PDD's Temu. USPS said letters and flat mail from China and Hong Kong would not be affected, according to a statement on its website.

Potential reasons behind the suspension could be to ensure the tariff is enforced and not bypassed by potential loopholes such as exporting multiple packages of smaller value items (see more here).  While it's not clear what prompted the move, it followed Trump's decision to revoke a "de minimis" rule for China, which previously allowed small packages under $800 to enter the US duty-free. This exemption, often used by Chinese-linked e-commerce companies, was removed as part of a new 10% tariff on goods from China and Hong Kong, which took effect just after midnight Tuesday Washington time.