Chris Heaton-Harris wrote to universities requesting copies of any syllabus and online lectures relating to Britain’s exit from the EU

The government whip who asked every university for the names of academics teaching about Brexit faces a formal investigation into the claim that he was researching a book on Europe.

Chris Heaton-Harris, who was accused of “idiotic Leninism” after the letters came to light, has been referred to the Commons standards watchdog over allegations of “abuse of parliamentary facilities”.

Jo Johnson, the universities minister, insisted that Mr Heaton-Harris had been pursuing an “academic inquiry” that may “lead to a book on these questions”. However, Tom Brake, the Liberal Democrat Brexit spokesman, said that because a book is “a private activity for which he might reasonably be expected to earn money”, Mr Heaton-Harris might have breached the MPs’ code of conduct by using parliamentary headed notepaper