Opposition parties are challenging the Government to match US President Barack Obama's determination to tackle greenhouse gas emissions.
He's declared "a war on coal" and says US power plant owners must cut carbon dioxide emissions by 32 percent from 2005 levels by 2030.
"It's the biggest, most important step we've ever taken," Mr Obama says.
"No challenge poses a greater threat to future generations than climate change - there is such a thing as being too late."
Green Party co-leader James Shaw says Mr Obama is showing real leadership.
"In many ways the energy sector is to the US what the agricultural sector is to New Zealand," he says.
"If Obama can come up with a plan to reduce energy emissions, then New Zealand should be able to come up with a plan to reduce agricultural emissions."
Labour's Megan Woods says the move shows leading nations are mustering the courage to do what's necessary.
"New Zealand is equally capable of tackling sectors where we could, and should, do better," she says.
"His plan is nothing short of brave... it seems Prime Minister John Key would prefer to sit on his hands and wait for everyone else to fix this problem for us."