At the same time, the U.S. and China are exchange verbal salvos over cyber espionage, the government of Yunnan province in western China said it is investigating Coca-Cola over allegations that it illegally mapped parts of the region, according to a report in the Financial Times.

The Yunnan Geographical Information Bureau of Surveying and Mapping said the U.S. beverage company had been "illegally collecting classified information with handheld GPS equipment,” according to a Yunnan government website.

Coca-Cola said it had "co-operated fully" with the inquiry, adding that local bottling plants use "e-map and location-based customer logistics systems that are commercially available in China" to improve customer service and fuel efficiency.

The Yunnan government said the Coca-Cola case was one of 21 instances of alleged illegal surveying under investigation in the area, which also included others' illegal sales of classified military maps online, aerial photography by unmanned aircraft, and illegal surveying of military bases.

The bureau gave no further details of the Coca-Cola investigation, according to the Financial Times report, but a bureau official who gave his surname as Han said the investigation would end soon. "We will announce the results when it ends," he told the Financial Times in an interview. "It is a bit sensitive. I don't know how it got published," he added.

China National Radio broadcast an interview with Li Mingde, the deputy director of the Yunnan bureau involved in investigating Coke, who said it was "urgent" to punish cases of illegal mapping.