The Government has formally gazetted its policy to halve greenhouse gas emissions from 1990 levels by 2050.
Climate Change Minister Nick Smith says the move delivers on the National Party's 2008 election promise.
Dr Smith says recent consultation supported setting a long-term emissions reduction target, but he says halving New Zealand's emissions over the next 40 years will require major changes in the economy.
He says the target will be regularly reviewed to take into account the latest science, the development of new technologies and progress by other countries.
