From BBC political editor Nick Robinson's blog today: "It is now clear that phone hacking at the News of the World was much more widespread than previously thought; that it targeted senior ministers not just celebrities and that, if the Guardian is correct, at least one of the paper's executives knew about it. This is leading to calls - not just from Labour politicians - for Andy Coulson to answer questions about what he knew and to questions about whether he should be at David Cameron's side.
"That is why I am sure that David Cameron is anything but "relaxed", as was claimed last night.
"Coulson has already broken rule one for any spin doctor - "Never become the story". He's good enough at his job to know that this story will soon become one about David Cameron's judgement."