A veteran TV reporter has sparked outrage over his “sexist” questioning of New Zealand's pregnant Prime Minister about the conception of her baby.

Charles Wooley described Jacinda Ardern as attractive and called her the “catch of the day” during the interview for 60 Minutes on Australia's Channel 9.

Asking what he called a “really important political question", the 70-year-old said: "What exactly is the date that the baby’s due?”

The 37-year-old, who became New Zealand's youngest prime minister in over a century in October last year, told him that it was 17 June.

Ms Ardern grimaced and her partner Clarke Gayford blushed as the journalist commented: "It's interesting how many people have been counting back to the conception"

Wooley continued: “Having produced six children it doesn't amaze me that people can have children - why shouldn't a child be conceived during an election campaign?”

The Prime Minister appeared to roll her eyes as she replied: “The election was done. Not that we need to get into those details.”

Wooley was quickly condemned by viewers in Australia and New Zealand as a “national embarrassment” and an “outdated dinosaur” who should retire.

His interview was also derided as “cringeworthy”, "pathetic" and “gross”.

Defending his interview, Wooley described the criticism on social media as “Orwellian”.

He said: “I just loved being with them, I thought they were so much fun, such a breath of fresh air, you know it was just terrific to be with them”.

He admitted his wife had accused him of “gushing” but said: "If you say somebody is attractive, my thesaurus defines it as 50 choices from good looking to gorgeous to likeable, there is so many different meanings."

Ms Ardern told a press conference that it was a case of “too much information” but said she was not offended.

“At the time certainly, I think that question threw me a little bit, but it would be going a bit far to say I was somehow offended by it," she said. "I wasn't. “Maybe I've lost all of my sensitivity, maybe it's just that I'm from Morrinsville, I don't know, but I just wasn't particularly fazed by any of it."