Boris Johnson committed an unambiguous breach of the rules when he failed to get permission from the ministerial appointments watchdog before taking a job as a Daily Mail columnist, which has led to calls for reform of the “good chaps” system. The former prime minister was unveiled as a writer for the newspaper earlier this month, but he only told the Advisory Committee on Business Appointments (Acoba) half an hour before the appointment was made public. Eric Pickles, the Conservative peer who chairs Acoba, wrote to the government on Tuesday setting out the case for reforming the rules, as the watchdog currently has no powers to impose a sanction on the former prime minister. In his letter to Oliver Dowden, the deputy prime minister, Pickles said Johnson’s case was a “further illustration of how out of date” the rules were, saying there must be sanctions for breaches. “They were designed to offer guidance when ‘good chaps’ could be expected to observe the letter and spirit of the rules,” he said. “If it ever existed, that time is long past and the contemporary world has outgrown the rules.” Pickles added: “What action to take in relation to this breach is a matter for the government … I suggest that you take into consideration the low-risk nature of the appointment itself, and the need to reform the system to deal with roles in proportion to the risks posed.” Under the ministerial code, former ministers are supposed to ensure that no new appointments are announced, or taken up, before Acoba has been able to provide its advice. The Mail unveiled Johnson as a columnist a day after a damning report found he deliberately misled the Commons and was part of a campaign to intimidate MPs who investigated him. The paper’s announcement was accompanied by a video in which Johnson said the column would be about “exactly what I think about the world”. “It is going to be completely unexpurgated stuff. I am going to be writing whatever I want. I may even have to cover politics from time to time but I will obviously try to do that as little as possible unless I absolutely have to,” he added. His first column was about his use of a medicine to help him lose weight. Johnson was previously paid a £275,000 salary to write for the Telegraph. He also faced censure from Acoba for failing to seek advice from the committee before joining the Telegraph, after he resigned as Theresa May’s foreign secretary.