US national security adviser warns UK about Huawei 5G tech

O’Brien said the move could lead to hacks of the UK’s secret intelligence services, reported the Financial Times on Tuesday.

He said that the UK risked giving the Chinese Communist party access to the “most intimate” details of British citizens and the ability to steal national secrets.

"They are just going to steal wholesale state secrets, whether they are the UK's nuclear secrets or secrets from MI6 or MI5," O'Brien told the FT.

“It is somewhat shocking to us that folks in the UK would look at Huawei as some sort of a commercial decision. 5G is a national security decision,” he added.

The United States has been pressing nations not to grant Huawei access to 5G networks, arguing that the company could use its tech for spying on western governments for Beijing.

Huawei has repeatedly denied these claims.

Washington had already banned companies in the US from using telecommunications equipment made by firms that could pose a national security risk.

British security officials last year concluded that any risk from Huawei could be mitigated if it were barred from the network's “core”, but US officials disagreed with that assessment.

Australia has also urged the UK to exclude Huawei from its 5G networks due to the sensitive information that it shared with US, Canada, Australia and New Zealand.

In the past, the US had gone as far as to warn that allowing Huawei into 5G networks could limit intelligence sharing.