"It gets a little bit tedious having to say that you didn't. And I didn't. I didn't give it to anyone else. They have gone through my office and looked and questioned my staff and they have all been honest.
"As soon as I heard it I went, right, this is controversial, this is great gossip - I can't tell a soul. Because it is a great one to yack about."
Bennett appeared on The AM Show with Labour's deputy leader Kelvin Davis, and both said the negotiations with Peters could go either Labour or National's way.
Davis said 54 per cent of people voted for change.
"And that's why we're in this situation we are in. We are waiting now for the special votes to come in and the negotiations will start in a few weeks.
"I've got immense respect for Winston and we are giving him the time and space that's needed. I haven't spoken to Winston and to my understanding Jacinda hasn't yet."
However, Bennett said National was clearly the biggest party, picking up 46 per cent of the vote to Labour's 35.8 per cent.
"Imagine if it were Labour that was on 46 per cent. Would you be sitting here and saying 54 per cent of people had voted for no change? It would be a really different equation if it were the other way around and the way the left are spinning it is quite funny."
Bennett expressed frustration with MMP.
"I'm exhausted to be quite honest with you. I got to election night and like most of my colleagues absolutely spent. It is a week later and you go, 'God, it's a crazy system we're in'."