The UK has no easy way to block China’s ambitions to export nuclear reactor technology to Britain on security grounds, despite growing public anxiety about Chinese involvement in sensitive infrastructure, according to people familiar with the situation.

The government’s willingness to permit the state-owned utility, CGN, to participate in the UK’s nuclear power generation programme has raised eyebrows in recent months as Chinese investment has come under hostile scrutiny, both in Europe and the US.

In October, an assistant US secretary of state, Christopher Ashley Ford, even warned the UK explicitly against partnering with CGN, saying that Washington had evidence that the business was engaged in taking civilian technology and converting it to military uses. More recently, concerns about the Chinese telecoms company Huawei and cyber security have also prompted calls for the government to back away from closer energy ties.