Chloe Swarbrick takes down troll after 'compliment' on breasts

At 23, Green MP Chloe Swarbrick is an expert when it comes to social media - and responding to sexist trolls.

New Zealand's youngest MP in 42 years posted a photo of herself and founding co-leader of the Green Party, Jeanette Fitzimons, to her official Facebook page on Friday.

While many of the comments were politically charged, only one resorted to misogyny.

"Nice tits!" wrote a man named Terry, a degrading comment presumably directed at 73-year-old Ms Fitzsimons.

Ms Swarbrick didn't let the commenter's nastiness go unchallenged, responding to him directly with a dignified yet devastating put-down.

"I thought long and hard about deleting your comment," she wrote. "Not the least because it's heavily insulting to somebody who has dedicated their life to improving all of ours.

"However, given that your comment is indicative of so many that myself and a number of women with platforms have received (notably often also by way of DM), I think I'll leave it here for people to contemplate what we as a society treat as acceptable behaviour for grown men.

"I hope you too find a moment to reflect on how this culture impacts on the women in your life," she signed off. "Cheers."

Terry didn't back down, retorting that he made the remark because he dislikes the Green Party and it was "the only comment I saw as fitting". Others jumped in to condemn his "shameful weird" behaviour.

"The most concerning thing about your response here is that it suggests you believe women are only worthy of not being sexualised if they provide some other value to you," one commenter wrote.

Female politicians in New Zealand are often the subject of sexist comments and violent threats on social media.

In a recent Facebook post advertising a live Q&A with Golriz Ghahraman, Newshub Nation had to intervene to remind commenters that racism and misogyny were unacceptable.