Washington, May 1 : The US Chamber of Commerce has warned that rising scrutiny of American firms in China "dramatically increases" the uncertainties and risks of doing business in the country.

The influential business lobby said Friday it was closely monitoring “heightened official scrutiny” of US firms by the Chinese authorities, following the questioning of employees at management consultancy Bain & Company in Shanghai and the shutdown of the Beijing office of due diligence provider Mintz Group.

“The services these firms provide are fundamental to establishing investor confidence in any market, including China,” the chamber said in a statement, without naming either company.