The Prime Minister has had the heat put on him by Opposition parties about his relationship with Whale Oil blogger Cameron Slater during the first question time since the Dirty Politics book was published.
MPs sat in the House for the first time since the election and the commencement of the 51st Parliament this afternoon.
Green Party co-leader Russel Norman led the attack on John Key, asking him how many times he had spoken to or sent text messages to Slater since November 2008.
"None in my capacity as Prime Minister," Mr Key replied.
"I think it's been well-established in this House for a long period of time that Prime Ministers wear a variety of different hats – that includes as leader of the National Party, and can include as a citizen.
"I happen, for the record, to use my ministerial service-funded cellphone to ring my wife. When I ring my darling wife and I put the cat out at night, I do that in my capacity as a husband, not as Prime Minister."
Investigative journalist Nicky Hager's book, released in August, drew connections between Slater and National Party staff members and Ministers.
The book says Slater was fed information from National Party sources to use in attack posts on his blog.
Mr Hager's book was based on communications taken from Slater after his site was hacked following a comment he made about a West Coast crash victim being "feral".
It documents a conversation Slater had on Facebook in which he said Mr Key called him "to commiserate" about the man's mother who had also confronted him during Pike River meetings.
Mr Key said he wasn't "100 percent sure" of whether he called Slater using his ministerial services-funded cellphone and did not want to discuss conversations he had other than the ones in the capacity of Prime Minister.
New Zealand First leader Winston Peters joined in, saying he believed Mr Key's answer was "particularly disturbing".
"It would appear any minister could make this claim and say 'not in my capacity as a minister'."
Dr Norman asked whether it would set a standard for Mr Key to ask his staff to no longer contact Slater.
"I've made it clear that we don't endorse many of the stories or comments run by a range of different bloggers, but no, I won't be telling them to do that," Mr Key said.
He said the party talked to bloggers because they are part of the media landscape which is the same as other parties.