The US argument that Huawei installed equipment will mean the Chinese state can spy on them is weak at best. There was a Panorama show about this very thing on the BBC this week. The GCHQ take on it is that spying would not be an issue. Anything sensitive would be encrypted anyway, so even if the Chinese were syphoning of data they wouldn't get anything of use. And although weaknesses are there in the security of the software on the Huawei 5G kit, it is more about bad coding than deliberate backdoors.
They do have other worries that they could be used to create DDOS style attacks on the UK network infrastructure but not about the Chinese spying.