In a major speech this morning on cleaning up politics, Cameron launched a surprisingly bold attack on lobbying, effectively blaming lobbyists for declining levels of public trust in Parliament.
He said: ‘It's an issue that crosses party lines and has tainted our politics for too long...an issue that exposes the far-too-cosy relationship between politics, government, business and money. I'm talking about lobbying - and we all know how it works.
‘The lunches, the hospitality, the quiet word in your ear, the ex-ministers and ex-advisers for hire, helping big business find the right way to get its way. In this party, we believe in competition, not cronyism. We believe in market economics, not crony capitalism. So we must be the party that sorts all this out.
‘Today it is a £2bn industry that has a huge presence in Parliament. The Hansard Society has estimated that some MPs are approached over one hundred times a week by lobbyists.
‘I believe that secret corporate lobbying, like the expenses scandal, goes to the heart of why people are so fed up with politics. It arouses people's worst fears and suspicions about how our political system works.'
Cameron also unveiled plans to double the current ‘quarantine' period during which ministers are barred from taking private sector jobs after leaving office (from 12 months to two years).
Today's speech will send shockwaves through an industry that has already faced strong demands to become more transparent in recent months. MPs on the Commons public administration select committee have repeatedly called for greater regulation of lobbying, but the Government has so far refused to impose statutory regulation on the industry.
London Evening Standard deputy political editor Paul Waugh suggested that Labour had missed a trick and that the Tory leader's attack on lobbying could be a vote winner:
‘Here is an issue that - despite lobbyists' attempt to target the Tories more than Labour in recent months - Labour should be kicking itself for not taking a lead on. Lobbying has for many ruined politics in the US and here's a chance to put a distinctly British stamp on it.'
Today's speech also follows last week's news that many MPs have booked dining rooms in the House of Commons for lobbying firms.
Writing on his blog, Waugh said: ‘There are, of course, plenty of lobbyists who behave honourably, and not just for charities or other single issue groups. But this is an issue, as last week's "banqueting list" showed, is now so extensive that it requires the disinfectant of sunlight.'