The allegations against Tim Yeo come just a week after another Conservative MP, the backbencher Patrick Mercer (pictured), was forced to resign the party whip after being caught up in a another set of lobbying claims.
As a result of those claims, the Speaker, John Bercow, reportedly suspended more than 80 House of Commons passes and the government promised to bring forward a bill to introduce a statutory register of political lobbyists.
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Former shadow foreign secretary Hilary Benn led calls by a series of senior Labour MPs urging colleagues to 'win' back the party.
A team of detectives and specialists is set to begin a painstaking excavation of the area where Ben is thought to have gone missing in 1991.
The foreign secretary's suggestion last week's bombing of an aid convoy might constitute a war crime prompted an angry response from Moscow.