The business secretary, Kwasi Kwarteng, has told the Competition and Markets Authority (CMA) to investigate the planned acquisition of Pepetuus Group by an academic and a company called Taurus International.

Kwarteng said he had issued the public intervention notice “on the public interest ground of national security”. The department has concerns about the implications of the takeover because while Perpetuus has just 14 employees and reported a turnover of £479,000 in the year to March 2020, it supplies “at least one-quarter” of all graphene plasma goods in the UK. Kwarteng has said that foreign investment in the UK “must not threaten national security”.

Perpetuus is working on applications for graphene, which has been frequently described as a wonder material thanks to its superlative properties. It says it has used its technology to strengthen bicycle and car tyres and it is developing “graphene-enabled” batteries and a method for producing surface...