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.
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"It is simply not acceptable for Huawei to be creating the backbone of the domestic telecommunications network in the United States, period," he said, a principle that he said also applied to U.S. allies.
Australia refused to allow Huawei to bid for work in building its National Broadband Network, despite an extensive lobbying campaign by the Chinese company.
In the UK on Thursday, Whitehall officials announced leading security officials would examine the workings of the Cyber Security Evaluation Center in Banbury, which was established three years ago by Huawei.
Last month, parliament's Intelligence and Security Committee issued a scathing report about the center, which was set up to examine the physical equipment and software used by Huawei, and assure that it is not vulnerable to cyberattack.
The ISC concluded it was "highly unlikely to provide, or to be seen to provide, the required levels of security assurance," and was surprised that the staff given the task of vetting the intricate inner workings of Huawei's highly complex equipment were paid for, and managed by, the Chinese group.
Security analysts have long feared that Chinese government links to the company mean that any nation embedding Huawei's equipment in its telecoms infrastructure might be vulnerable to cyber espionage by Beijing.