Wuxi Biologics suspended trading in Hong Kong on Tuesday following a record slump in its share price, after Washington added the Chinese pharmaceutical giant to a list that could restrict its US operations.

The Department of Commerce on Monday said the company was among 33 Chinese entities added to its unverified list, which may force it to obtain additional licences to do business with American firms.

Wuxi Biologics, which produces vaccines and drugs on contract for pharmaceutical firms, said the move would have "no impact" on its business and that it was "in compliance with all US export control regulations".

But its shares plunged as much as 32 percent in Hong Kong on Tuesday before suspending trading down 23 percent at HK$62.25.

Wuxi Biologics has suspended trading in Hong Kong after a US listing triggered a record slump in its share price
Wuxi Biologics has suspended trading in Hong Kong after a US listing triggered a record slump in its share price AFP / ISAAC LAWRENCE

The company has expanded aggressively in recent years with a 1.3 million-square-foot production facility set to open in the western Chinese city of Chengdu next year, according to its website.

It signed an agreement with GlaxoSmithKline and Vir Biotechnology to produce Covid-19 antibody treatment Sotrovimab in 2020, and took over a Bayer factory in Germany last year to produce Covid-19 vaccines.

The United States has added a number of Chinese companies to official lists in recent years, curtailing their ability to do business at a time of heightened tensions between the world's two biggest economies.

China's commerce ministry on Tuesday said it "firmly opposed" the latest US move, calling the list a "tool of political suppression and economic bullying".

The addition of Chinese tech giant Huawei to the so-called entity list -- as well as subsequent moves against the telecom giant -- have barred it from buying crucial components and decimated its once-thriving smartphone business.