National leader Simon Bridges has admitted liking a tweet by blogger Cameron Slater which mocked the Prime Minister's partner Clarke Gayford - but he claims it was an accident.
Mr Slater, who runs the controversial right-wing blog Whale Oil, tweeted an old picture of Clarke Gayford with the caption 'fish of the day' on Sunday evening.
The photo features Mr Gayford dressed in what appears to be women's clothing.
Mr Bridges liked the tweet, but says he did not do so intentionally.
"I'm not on Twitter very often and I think this shows why," he said on Wednesday afternoon.
"I was scrolling down and I saw the tweet there that you're referring to. I noticed it, I accidentally liked it, I got rid of that within literally a second and kept on moving."
Mr Bridges says he's "regretful" that it happened, adding "too much tweeting maketh a twat".
"I've been really clear with my caucus colleagues that we don't want families brought into politics," he said.
Mr Slater and his blog were a central focus of journalist Nicky Hager's book Dirty Politics, but the blogger denied its claims.
When asked why he follows the blogger Mr Bridges said: "Well I don't know if I do, truthfully I'm just on Twitter very rarely."
Mr Bridges does follow Mr Slater on Twitter, as do a number of politicians.
The National leader said he'd be happy to offer an apology to Mr Gayford "if it was required".