Giving the Chinese telecoms firm Huawei a role in building the UK’s 5G network poses an unnecessary risk to national security, a former MI6 chief has said.

Sir Richard Dearlove said such a move could give the Chinese government a “potentially advantageous exploitative position” in the UK’s telecoms network. It follows reports last month that the PM is ready to let the firm supply some parts of the UK’s 5G infrastructure.

A Huawei spokesman said Sir Richard’s warnings were “short on fact”.

Sir Richard’s intervention comes as US President Donald Trump signed an executive order effectively banning American firms from using foreign telecoms deemed to pose a threat to national security.

Although it does not name Huawei, it is widely considered to be aimed at the firm following repeated warnings by US officials that it could be used by the Chinese state to spy on or sabotage foreign networks. The company has vehemently denied the allegations and insists it is independent from state control.

In a foreword to a new report by the Henry Jackson Society think tank, Sir Richard said: “The fact that the British government now appears to have decided to place the development of some of its most sensitive critical infrastructure in the hands of a company from the People’s Republic of China (PRC) is deeply worrying. “The PRC uses its sophisticated technical capabilities not only to control its own population (to an extreme and growing degree), but it also conducts remotely aggressive intelligence gathering operations on a global scale. “No part of the communist Chinese state is ultimately able to operate free of the control exercised by its Communist Party leadership. “To place the PRC in a potentially advantageous exploitative position in the UK’s future telecommunications systems therefore is a risk, however remote it may seem at the moment, we simply do not need to take.”

Last month, former defence secretary Gavin Williamson was sacked after details about Huawei’s potential involvement in the UK’s 5G network – discussed at the National Security Council – were leaked to the Daily Telegraph. In the paper’s report, Mrs May was said to have overridden ministers who had expressed concerns about the plans. Mr Williamson has strenuously denied leaking the information.

The government has insisted no final decision has been taken on Huawei’s involvement in the UK network, although the issue remains highly sensitive in Whitehall.

Sir Richard said the government – which has been seeking to build economic links with China – should not be influenced by fears of economic reprisals by Beijing if Huawei is excluded. “If Australia can blackball Huawei as its 5G provider, the UK can certainly do the same without undue concern about the consequences,” he said.

A Huawei spokesman said: “This report is long on politically motivated insinuation but short on fact. “It fundamentally misunderstands the nature of modern China, global technology markets and of 5G. “The isolationist approach they recommend may support an America-first trade agenda but it’s hard to see how it’s in UK’s national interest.”

A government spokesman said individual countries were taking “a range of different approaches” to the issue of 5G security.

“There are no universal solutions,” the spokesman said. “Whatever final decision the UK government takes about 5G network infrastructure, the UK is not considering any options that would put our national security communications at risk, within the UK and with our closest allies.”