MP Patrick Mercer quits whip after BBC secret filming
31 May 2013 Last updated at 22:36 BST
The Conservative MP Patrick Mercer has resigned from his parliamentary party and will step down at the next election, over a BBC Panorama investigation into lobbying by politicians.
It is alleged Mr Mercer accepted money and asked questions in the Commons in breach of parliamentary rules.
The Newark MP said he had made the decision to step side to save his party embarrassment but is consulting lawyers.
For David Cameron these allegations are an unwelcome echo of the cash for questions scandal that rocked Parliament in the mid nineties.
Mr Mercer says he agreed to undertake consultancy work outside Parliament
Iain Watson reports.