The UK's cyber-defence watchdog has confirmed it has blacklisted one of China's leading state-owned companies.

The National Cyber Security Centre (NCSC) has written to UK telecoms providers warning them that the use of ZTE's equipment and services could pose a national security risk.

The move coincides with a US government ban preventing American businesses from selling components to the Shenzhen-based company.

ZTE has yet to respond.

"It is entirely appropriate and part of NCSC's duty to highlight potential risks to the UK's national security and provide advice based on our technical expertise," said a statement from Dr Ian Levy, the organisation's technical director.

"NCSC assess that the national security risks arising from the use of ZTE equipment or services within the context of the existing UK telecommunications infrastructure cannot be mitigated."

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