Watch: 'The day I stop to think about the ACT Party ...I'll check myself into a lunatic asylum' - Winston delivers two fingers to David Seymour

Winston Peters has taken a big swipe at David Seymour's ACT Party today, saying he would check himself into a lunatic asylum before even thinking about the party. 

The confident NZ First leader today called this election "a three way fight". Source: 1 NEWS

His remarks came after 1 NEWS' Jessica Mutch had asked Mr Peters a question about ACT, while in Auckland today.

Mr Peters had shot back: "The day I stop to even think about the ACT Party, is the day I think I’ll check myself into a lunatic asylum."

For more on this story, watch 1 NEWS at 6pm. Source: 1 NEWS

He finished with, "thank you very much", before heading towards the NZ First bus, but then turned around to add: "They don't matter in this campaign.

"This is a three-way fight and you'll find that out."

It was big talk against a party that could yet be a coalition partner with Peters' NZ First - and National, after this Saturday's election.

A no-show at 1 NEWS' multi party election debate last night, Mr Peters went on the attack today. Source: 1 NEWS

It's not the first time Mr Peters has attacked ACT. Just over a week-ago he labelled Mr Seymour a "badly bred dog that barks at everything that goes by", after the ACT leader criticised Mr Peters' decision to pull out of the TVNZ minor party debate. 

Mr Seymour was at Business NZ conference in Wellington, when he criticised NZ First MP Richard Prosser. Source: 1 NEWS

In August, Mr Seymour called NZ First MP Richard Prosser a "F**king idiot".