Ensuring that products and components keep pace with technological development is crucial to maintaining network security, the letter said. The US action upgrade against Huawei may affect its ability to provide updates to products containing US technology.
A spokesman for the UKs National Cybersecurity Centre said the centre provided operators with a range of possible preventive measures and was also carefully considering the impact of the US sanctions on UK networks.
BT and Vodafone did not comment. A Huawei spokesman said the company was working fully with the UKs national cyber security center and declined to comment further immediately.