Keisha for Prime Minister?

All hail actress and climate change campaigner Keisha Castle-Hughes who has hit back at John Key after the Prime Minister told her to "stick to acting".

The Whale Rider star, who is an ambassador for Greenpeace, appeared on last night's edition of Close Up to defend her stance on the environment.

The Oscar-nominated mum-of-one admitted she was taken aback by Key's brush-off when he addressed a business meeting in Brisbane yesterday and made light of her work as an advocate for the charity's Sign On campaign.

"I personally thought it was an odd forum for my name to come up," said Keisha, 19, on the show. "The only thing I can think of is that this week it's a really important week with the Pacific Island forum and I think that it's the first time that climate change has been a major issue [there].

"I don't envy John Key, I don't envy any prime minister's position at a time like this with climate change going on and having to take action now. It can't be easy but it's really important to stand up and take notice.

"I'd love to sit down and maybe if we sat down and talked he'd know that I know a lot more about it than he thinks I do."

The star also took to her blog for Greenpeace to add to her comments during her TV appearance.

"Climate change is a global issue that affects our country as a whole," she wrote. "Before being anything else in my life, I am a mother, and that is why I am a part of this campaign.

"And as a mother I believe I have a right to speak up if I have concerns about the future of my daughter. Discouraging New Zealand youth to participate, think and speak out is not on for the Prime Minister of NZ."

Keisha, who recently went on a fact-finding mission to the Cook Islands to witness the effects of global warming there first-hand, accused John Key of not listening to public opinion.

"John Key's climate change minister Nick Smith has spent the last two weeks running a public consultation on what NZ should do on climate change," she wrote. "I was under the impression that the NZ Government was therefore interested in what the public had to say. Is the PM all of a sudden NOT interested in public input?

As mentioned, Keisha's part of the Sign On campaign, which calls for a 40 per cent reduction in greenhouse gas emissions by 2020, which is also supported by Kiwi actresses Robyn Malcolm and Lucy Lawless - who weren't singled out by Key for a mention.

But kudos to the girl for not being drawn into a tit-for-tat row with this country's leader, adding on Close Up, "The only message I have for him right now is that I think that this week at the Pacific Island Forum is the time to commit to that target.

"Al Gore came out and said that now is a time that isn't about changing lightbulbs, it's about changing laws. And that's why it's a really important time for governments to come forward and to commit to the 40% reduction in the emission target by 2020."