Jacinda Ardern has revealed that a man she did not know sent her photos of his genitals on Twitter.

The Prime Minister had called into ZM's Fletch, Vaughan & Megan show for her regular interview. It was during a discussion about a new law passed in Texas which fines people $500 if they send unsolicited photos of their privates where Ardern made the revelation.

Fletch had just quoted the statistic saying that 40% of women had received unsolicited X-rated pictures.

"I reckon that's a bit low," Ardern answered. "I consider myself to live a pretty tame life and someone while I've been a politician tweeted a pretty... lewd doesn't even capture what that photo... it was just..."

As she searched for the right word to describe the unwanted photo Fletch jumped in seeking clarification.

"Has somebody slid into your DMs with a naughty picture?" he asked, referencing the act of sending a direct message to someone you don't know.

"Ah, yeah. Yeah," Ardern said, before elaborating. "This is quite a while ago but the thing that surprised me the most was there was quite a recognisable tattoo."

"If you're gonna do something anonymously don't have any identifying body features," she added.

"We call that the 'Fletch Proposition'," Vaughan said. "You never have any identifying features in the same photo, like the face, tattoos, in the same photo as your genitals."

"Yeah, yeah," laughed Adern, before rating the man's efforts.

"A massive fail there."