He said the expenses revelations had shown the “clawing greed” of MPs and revealed how Westminster had been taken over by “a culture of abuse”.

His devastating attack came as Parliament’s former anti-sleaze chief also accused MPs of a failure of “moral leadership”.

Lord Carey wrote: “It is not just the clawing greed of painstaking claims for such minor items as tampons, barbecue sets and bathrobes, but also the egregious way some have transferred allowances from one second property to another – enabling them to refurbish homes at public expense, then sell them for profit.

“Already our MPs are seeking a scapegoat. The first reaction was to shoot the messenger, blaming so-called chequebook journalism. Yet they’ve only themselves to blame. The moral authority of Parliament is at its lowest ebb in living memory.”

Coming at a time of financial crisis and the betrayal of the Gurkhas, anger over politicians’ allowances “threatens to be the straw that finally breaks the camel’s back,” Lord Carey said.