Top MP takes aim at 'timid' Cam & Clegg.
Ex-Foreign Office Minister Jeremy Browne will criticise the pair for shirking tough decisions and urge them to be "bolder" with projects such as airport expansion.
In his book Race Plan, he warns Britain is set to fall behind China unless his Lib Dem boss Mr Clegg and the Government boost public services and the economy.
A source close to the MP for Taunton Deane, Somerset, said: "Jeremy feels they have been too timid."
A Cabinet source said he was "entitled to his views" but added: "I'm not sure his former colleagues will have time to read them."