In a non-denial denial, a Downing Street spokesman merely says "we do not recognise this at all".

The Tory MP the right wants to replace Tim Yeo as chair of the energy and climate change committee has been paid £70,500 by oil company Tethys Petroleum since 2012.

The PM's decision to reject calls for a "viable cheaper option" represents an opportunity for Labour to woo the Lib Dems.

The PM declared in 2010: "No ifs, no buts, no third runway".