'Jackals' will come for Bennett and Bridges - Peters

Winston Peters doesn't think Simon Bridges will be still be leading the National Party at the next election.

Mr Bridges is struggling to get traction with voters, languishing in single figures in opinion polling as preferred Prime Minister.

He'll be hoping this weekend's National Party annual conference and kind words from former Prime Minister Sir John Key will give him a boost, but the Acting Prime Minister doesn't think it'll be enough.

Mr Peters told Newshub Nation on Saturday the "jackals" will be after him - but not before taking out his deputy.

"I predict the first person they'll come for is Paula Bennett, because that's what jackals do. They don't go for the biggest animal - they go for the smallest and weakest one. And then it will be Simon."

Labour suffered a revolving door of leaders in the post-Helen Clark years while in Opposition, not recovering until the last-minute selection of Jacinda Ardern before the 2017 election.

Mr Peters says National will suffer the same woes.

"I'm not going to do hypotheticals. The chance of Simon Bridges lasting until the next election... is not good. I've seen this, I've been there, I've seen the instability when a party loses like National, and the rollover of leadership is horrible."

Though he admits it may have been different if the National caucus had gone with someone else other than Mr Bridges.

"One of these days you'll look back and say 'he was right'. I'll tell you why Simon's gone - Simon's discovered so much of his past a bit like Columbus discovered America - by accident. First of all he turns up and decides he's a Maori - nobody knew that before he got there. Then he started looking for his iwi. Now he's discovered marijuana.

"You can't have too many discoveries like this before people start saying, 'But what does this man really think? What drives him down inside?'"

'You have no idea'

Ms Bennett responded to Mr Peters' jabs on social media.

"In my experience your opponents try to take out one of the strongest - Sorry Winston, you have no idea," she said.

"Tis true, I am smaller - but I've never felt stronger."

Ms Bennett lost a lot of weight, admitting in January she had undergone surgery to get a gastric bypass.

As for his own leadership prospects, Mr Peters says it depends on " a whole lot of things, including one's health, how fit you are, what the team thinks and most critically of all, whether your being there is critical to victory. That's what most critical."

Asked by host Simon Shepherd if he was fit and healthy, Mr Peters said he was.