U.S. imports of containerized goods from China tumbled 28.3% year-on-year in June, after higher tariffs on goods from the country's top ocean trade partner extended a steep drop that began in May, supply chain technology provider Descartes said Tuesday.

Overall U.S. container imports fell 3.5% from June 2024 levels, coming in at 2.2 million 20-foot equivalent units (TEUs). China imports totaled 639,300 TEUs last month, according to Descartes' analysis of bill of lading data from U.S. customs.

The retreat followed an extended run of near-record imports fueled by importers rushing in goods to beat tariff deadlines.

China's share of U.S. imports hit 28.8% in June, well below the July 2024 peak of 40%. As a result, popular imports from China, from furniture and toys to textiles and footwear, tumbled last month.

At the same time, imports from several Southeast Asian countries, including Vietnam, Indonesia and Thailand surged as retailers and other imports diversified sourcing.

U.S. ocean imports appear to be stabilizing after the 7.2% year-on-year drop in May, said Jackson Wood, director of industry strategy at Descartes.

Year-to-date, total imports through June are tracking 3.8% above 2024, though growth has slowed compared to earlier in the year, Descartes said.

"This isn't as bad as it could have been or as bad as we thought it was going to be," Wood said.

Still, uncertainty over U.S. tariffs is likely to persist.

The U.S.-China trade truce that lowered punitive tariffs is set to expire on August 10.

Trump on Monday signed an executive order extending the partial U.S. tariff rate reprieve on many countries, changing it from July 9 to August 1.