New Zealand's climate emergency is being slammed as an empty motion.

Environmental activist Greta Thunberg has taken aim at our Government. She has shared an opinion piece on Twitter, calling our climate declaration virtue signalling.

Greenpeace Programme Director Niamh O'Flynn says Cabinet needs to ban synthetic nitrogen fertiliser.

"It produces more emissions then our entire domestic aviation industry, and that's before it's even on the farm.

"So if our Government invested in a transition to regenerative agriculture, that would be a great step."

She says that the climate emergency declaration was a symbolic gesture that would have been fine a decade ago. 

"The rubber's really hit the road on climate change. It's now or never for action."

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