Huawei is banned from government contracts in the US "due to national security concerns", and only last week a US security committee report alleged that it "cannot be trusted to be free of foreign state influence and thus pose a security threat to the United States".

Citing anonymous sources, Reuters claims that the classified investigation found no evidence of spying but did say that using Huawei’s equipment could be risky because of security vulnerabilities in its technology.

Reuters also quotes a White House spokesperson denying that there was "any classified inquiry that resulted in clearing any telecom equipment supplier".

Huawei has long faced accusations of espionage, and has been banned from government contracts not only in the US but also Australia.

It has consistently denied all allegations against it. Of the recent US security committee report, Huawei said: "Despite our best effort, the committee appears to have been committed to a predetermined outcome."

The UK government, meanwhile, has been happy to work with Huawei. Last month, the company announced a $2 billion wave of investment in its UK operations, a move that was welcomed by Prime Minister David Cameron.

Huawei’s cyber security chief is John Suffolk, former CIO of the UK government.