Boris Johnson could lose the “red wall” general election seats he won from Labour if he does not address the “shameful” lobbying crisis engulfing Whitehall, a senior Tory MP has warned.
Sir Bernard Jenkin described the current row over lobbying as “corrosive” of public trust.
It comes amid criticism that David Cameron contacted ministers on behalf of collapsed finance firm Greensill.
A review has been launched of contacts between top officials and ministers.
Writing in the Observer newspaper, Sir Bernard warned Mr Johnson that former Labour voters who gave the prime minister their backing at the last election will “dismiss him” unless he can show he is more open, transparent and different to the “out-of-touch elite”.
“There is nothing wrong with a private citizen wanting to make money, but we have a system that has allowed the lines between public service and private gain to become blurred,” Sir Bernard wrote, adding that it was “shameful”.
He said there had been a “failure of successive governments” to be more transparent about the relationships between administrations and business.
“This crisis presents an opportunity for a reset in politics and Whitehall, which could begin to restore public confidence,” he added.
A Downing Street spokesperson said the prime minister had commissioned an independent review – the findings of which would be made public.
After leaving office, Mr Cameron was employed by Greensill Capital and tried unsuccessfully to persuade the government to give the firm more access to government-backed loans.
The former prime minister is facing criticism for lobbying government ministers on several occasions on behalf of the firm, which he had a commercial interest in.
Meanwhile, it emerged last week that a former government procurement officer, Bill Crothers, joined Greensill as an adviser while still working as a civil servant. He got approval from the Cabinet Office.
Politicians from different parties have criticised the rules around lobbying.
Conservative peer Lord Eric Pickles said rules on ministers and top officials taking jobs with private companies needed urged reform, adding there did not seem to be “any boundaries” between civil servants and the private sector.
Labour leader Sir Keir Starmer said the current system is “not working” and that stronger lobbying rules are needed.
Agencies