ACT leader David Seymour has issued a warning to Chlöe Swarbrick after she won the Greens co-leadership.
The Greens confirmed on Sunday morning she's replacing James Shaw after she received 169 votes from Green Party membership delegates. Zero votes were cast for rival candidate Alex Foulkes.
Speaking on Sunday after the announcement, Seymour said he likes Swarbrick "on a personal level" - and offered her some advice.
"A massive salad of soundbites is not going to cut it. She's going to have to think deeper and harder about what solutions the Green Party's offering," he told media.
"I hope they will turn away from fueling envy and saying that there is some well-off people, that if we just took their money that would solve all our problems. That's not a real solution.
"They're going to have to start campaigning on solutions that grow the economy and make New Zealand a wealthier place. Otherwise, they're just playing this zero-sum game, drag them down.
"Sounds really good but it's not a pathway for a better New Zealand and it won't stand up to the scrutiny of being a leader."
In her victory statement, Swarbrick accused the Coalition Government of "bully boy behaviour".
"This week, the Government completed their cruel and, frankly, bizarre 100-day programme. They know that many of the things they have done will make things worse for people and planet and they've told New Zealanders that they don't care," she said.
Speaking alongside Seymour, National Party Revenue and Climate Change Minister Simon Watts said he didn't have a response to her claim but hoped Swarbrick would continue to work on Shaw's bipartisan approach to climate change.