New MP Greg O'Connor grilled after criticising Jacinda Ardern's handling of Clare Curran saga

Greg O'Connor has had a very stern phone call from the Prime Minister after criticising her handling of Clare Curran's resignation.

The first term Labour MP openly questioned his boss live on air in a radio interview, and there has been some fallout.

Ms Curran resigned as a Minister after scandals over private meetings and email use, saying the pressure was intolerable.

Now, Jacinda Ardern is under pressure from within her own ranks over how she handled the saga.

"It could've been done better, I don't think anyone will disagree with that," Mr O'Connor remarked in an interview with Newstalk ZB.

One of the Prime Minister's new MPs, Mr O'Connor was the one sitting in Ms Curran's seat when she took leave following her stumble in the House.

He seems confused about how exactly Ms Curran lost her job. She resigned, but Mr O'Connor said she was sacked - and even predicted Ms Ardern will have to swing the axe again.

"I'll tell you what, it'll be done better next time," he said.

Mr O'Connor's main gripe with the Prime Minister's handling of the Curran saga was an interview she gave on Friday morning, when she fudged whether she was cutting ties with the disgraced MP.

"There was a little bit of confusion about the interviews on Friday morning," Mr O'Connor told Newstalk ZB. "Yep, can't have that."

Ms Ardern says as a "confident leader" she's comfortable with her MPs openly criticising her, but has called Mr O'Connor for a 'please explain'.

Newshub understands he's assured Ms Ardern he has confidence in her handling of the saga.

This is perhaps a learning experience for a new MP that it's probably best not to criticise your boss about a sensitive topic on live radio - especially when your boss is the Prime Minister.