Chinese competition officials have met with their South Korean counterparts to discuss violations by US chipmaker Qualcomm, sources said, as Beijing reaches out to regulators overseas to complete a case that could result in record fines at home.

Qualcomm is one of at least 30 foreign firms to come under scrutiny as China seeks to enforce a 2008 anti-monopoly law - efforts some critics say have unfairly targeted overseas businesses, raising protectionism concerns.

The Korea Fair Trade Commission fined San Diego-based Qualcomm over $200m in 2009 for abusing its dominant market position.

But the stakes are bigger in China, where an investigation by the National Development and Reform Commission could trigger changes to Qualcomm's licensing deals and fines of as much as a tenth of a company's annual revenue.

Qualcomm had total revenue of almost $25 billion in the year to September 2013, about half of it in China.