David Cunliffe says John Key cannot resile from the controversial allegations made against the National Party in Nicky Hager's book Dirty Poltics.
The Labour leader says that when he read part of Mr Hager's book, which is aimed at bringing to light an alleged smear campaign being run by some of the Government's top ministers, he "felt almost physically sick and I think most New Zealanders would too".
Mr Cunliffe told TV ONE's Breakfast programme this morning that he found it hard to believe the Prime Minister had "no idea at all about the systems that are running in his own office".
Mr Key told Breakfast yesterday that he wasn't aware that his senior advisor Jason Ede had taken information from the Labour Party's website before Mr Hager's book was released.
He also said National had not hacked the website, and says he understands, from reading blogs on the matter, that the security was left off and Mr Ede became aware of that and he then went and looked through the site.
Mr Cunliffe told Breakfast that "whether or not the thing was properly locked makes no legal or practical difference".