China on Thursday said cross-border e-commerce remained competitive despite the scrapping of America's de minimis exemption for the import of small goods.

The removal of the exemption means that goods from Chinese retailers, especially e-commerce players, are now subject to the additional US duties on Chinese imports.

"No matter how a country adjusts its trade policy, the advantages and characteristics of cross-border e-commerce have not disappeared, and are still very competitive," said Commerce Ministry spokeswoman He Yongqian.

"At the same time, we hope that the US can follow the development trend of international trade, enhance supervision, and create a fair and predictable policy environment for the development of cross-border e-commerce."

The elimination of the duty-free exemption for low value packages and US President Donald Trump's order for an additional 10 percent levy on Chinese imports have caused confusion, with the US Postal Services reversing a decision not to accept parcels from mainland China and Hong Kong.

While tariffs on Chinese goods went ahead on Tuesday, Trump suspended his threats of imposing levies on Mexico and Canada.

Commenting on the move, He said Beijing is ready to work with other countries to "jointly respond to the challenges of unilateralism and trade protectionism".

"The unilateral imposition of tariffs by the US seriously violates World Trade Organisation rules. It is egregious in nature, and a typical unilateral trade protectionism that damages the rules-based multilateral trading system, disrupts the stability of global supply chains, and exacerbates international trade tensions," she said.

China does not proactively initiate trade disputes but will take necessary measures in response to one-sided bullying, He added.