The deputy head of a local chamber for small to medium-sized firms on Thursday said companies from mainland China and Hong Kong focused on e-commerce may still have profit margins, despite higher US tariffs.

US authorities began charging an extra 10 percent levy on top of existing tariffs, and cancelled a tax exemption for parcels with a retail value of US$800 or less.

A vice president of the Hong Kong General Chamber of Small and Medium Business, Stanley Lee, said while the tariff rise might have come abruptly, some products can still be competitive in the US market.

"For example, in traditional retail, it costs US$20 to buy an item. It's US$15 for them to buy on [American] online platforms, but it's US$10 on [Chinese] e-platforms before the rise," he explained to RTHK.

"So even with [25 to 35 percent extra tariffs], it's still cheaper to buy [Chinese products] than the traditional way."

Lee, who also heads the chamber's e-commerce policy committee, said his own firm was relatively unaffected by the new US policies, as his products are stored in warehouses on American soil and they clear customs regularly.

He said he expects some mainland e-commerce firms to do the same if they no longer find the parcel-mailing strategy profitable.

Lee added that companies mostly expected the trade spat to intensify, and have therefore turned to different markets in search for potential customers.