Did Donald Trump really think Jacinda Ardern was Justin Trudeau's wife?

Prime Minister Jacinda Ardern has clarified a claim that Donald Trump thought she was the wife of Canadian Prime Minister Justin Trudeau.

Comedian Tom Sainsbury told RadioLIVE on Sunday that he asked the Prime Minister about her recent overseas jaunt, where she met the US President for the first time.

"She said that Donald Trump was confused for a good amount of time, thinking that she was Justin Trudeau's wife," Sainsbury said.

However, the Prime Minister told The AM Show it was someone else that made that assumption, not Trump.

"I am clearly the partner of Clarke Gayford, which I'm sure the President of the United States is aware," Ms Ardern joked.

Ms Ardern said she found Trump "consistent".

"What you see is what you get, both in the public domain in and in the private."

Ms Ardern confirmed she exchanged friendly fire with Trump over the election.

Mr Trump told a person standing beside the Prime Minister: "This lady caused a lot of upset in her country", referring to the election.

She told the US President: "No one marched when I was elected," according to Newsroom.

Speaking to The AM Show on Monday, Ms Ardern said it was all in jest.

"I have to admit, as much as everyone thinks it was a burn, I didn't really think about it from his perspective, until I walked away about five minutes later.

"We were both having a laugh, I definitely know he didn't take it personally."

Ms Ardern said she was "not sure" whether Trump understood her joke.