Huawei has been a major supplier to British Telecom for seven years, providing equipment for BT's rollout of fibre optic broadband - one of the biggest infrastructure projects in the UK.

Huawei's equipment has also been used to help build Britain's 4G network being launched at the end of this month by E.E. The company also serves other big players in the UK mobile market.

Now the House of Commons Intelligence committee is evaluating BT's relationship with Huawei and whether it should give rise to concern.

The committee will report directly to Prime Minister David Cameron, seen here last month with Huawei's CEO Ren Zhengfei announcing new investments.

Huawei is putting two billion dollars into Britain over the next five years. Welcomed by David Cameron as exactly the type of business the UK wants.

Prof. Tommaso Valetti, Imperial College Business School, said, "They've created more than a thousand jobs...good business for the country as a whole "

The US House of Representatives Intelligence Committee this week called for Huawei to be excluded from doing business in the US on the ground their equipment could be used by the Chinese government or others. Behind it the fear that Huawei equipment is not secure.

The Shenzhen-based company has consistently denied all links with espionage and cybercrime and calls the allegations monstrous.

Huawei's operations in the UK are overseen by a body called the Cyber Security Evaluation Centre, agents of which operate inside the company's offices.

Prof. Annabelle Gawer, Imperial College Business School, said, "I think Chinese companies need to understand is a good example."

British Telecom says the work of the Security Evaluation Centre guarantees the security of their networks.