Former Tory frontbencher Patrick Mercer has announced he is quitting Parliament amid allegations he broke rules on lobbying.
The MP for Newark said he was resigning the Tory whip immediately "to save my party embarrassment".
He also made clear he will not stand at the next general election, due in 2015.
The move comes after a joint investigation by The Telegraph and the BBC's Panorama programme into an alleged lobbying scandal.
It is believed the allegations about Mr Mercer relate to "cash-for-questions" about Fiji and its suspension from the Commonwealth.