Western intelligence agencies believe that Huawei, the Chinese telecommunications giant, has spied on behalf of Beijing, an incendiary claim made by one of the U.S.'s most experienced espionage officers.
Michael Hayden, who headed the National Security Agency, the electronic eavesdropping body, and the CIA over nine years until 2008, said "at a minimum" Huawei shared with the Chinese state "intimate and extensive knowledge of the foreign telecommunications systems it is involved in."
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"I think that goes without saying. That's one reality," he said, in an interview with the Australian Financial Review.
Mr Hayden's comments go beyond what the U.S. government and Congress have said previously about Huawei, a private Chinese company which is also promoted by Beijing as a national champion in a strategic industry.
Huawei is one of China's most successful international enterprises but has run into obstacles in expanding its business in countries such as the U.S., the U.K. and Australia, which are all longtime intelligence partners.
The congressional House intelligence committee in an extensive report released last year called Huawei a threat to U.S. national security but made no direct accusations that the company was spying for China.
Mr Hayden said the burden of proof was on Huawei to convince western governments that its equipment was safe to use on sensitive networks in their countries.