Britain’s establishment, including politics, the media and big business, is “broken” and must be radically reformed, Nick Clegg claimed recently.

The Deputy Prime Minister is convening a round-table seminar with think tanks and democracy campaigners in Parliament to come up with fresh thinking to reform Britain’s institutions.

He will tell the group – expected to include the Electoral Reform Society, Unlock Democracy and 38 Degrees – that he is convinced of the need to reform. “I have looked at the institutions of our establishment close up,” he will say. “And I can tell you, I am more determined than ever to see them change. Britain’s broken establishment is now well past its ‘sell by date’.”

Mr Clegg will link the Parliamentary expenses scandal, the banking crash, party funding rows and the “sordid spectacle” of phone hacking.

The Liberal Democrat leader, who has faced criticism in the wake of declining poll numbers and local election setbacks, is expected to say Britain “is not broken at all”.

He will argue: “It is the British establishment that is broken. It is the institutions at the top that have let down the people.”