Labour Shadow Minister Gareth Thomas has put the boot in tonight:

“David Cameron has revealed how weak he is. He has failed to show leadership over serious allegations that Tim Yeo coached a witness to the Energy and Climate Change Committee, and used his position to further the interests of his clients. Tim Yeo has the right to defend himself but it is difficult to see how he can continue as Chair of the Select Committee pending investigation by the Parliamentary Standards Commissioner. If David Cameron won’t act then Tim Yeo should take it upon himself to stand down from his post.”

Tick tock, Tim.