Prime Minister Helen Clark says she is challenging other governments head-on over food miles, the controversy threatening to harm New Zealand's exports.
She said today one of the reasons she was making very strong statements about sustainability was because New Zealand needed to be a world leader to counter protectionism from competitors.
The food miles argument is being used to persuade overseas consumers that New Zealand's exports generate carbon emissions because of the long distances they have to travel.
It is also reaching into tourism as New Zealand requires long, carbon-emitting flights to reach.
To counter that, Helen Clark is focusing on New Zealand's lower-cost production methods, its efficiency and the Government's climate change initiatives.
"We can re-position. It is urgent. I've taken the food miles argument head-on myself," she said.
"I believe we're on sound ground but we will be on sounder ground as we show we are indeed a sustainable country."
Helen Clark said she had raised the issue with the British prime minister and foreign secretary and other leaders.
She was speaking to reporters after meeting John Ashton, the British Government's special envoy on climate change.
He said the "international conversation" about food miles had to become based on stronger evidence base rather than rhetorical politics.
"We do have to find ways of including the price of carbon in trade goods, but it's a very complex set of issues," he said.
"I understand the special circumstances that apply to New Zealand. In the end we need an equitable approach to this issue -- no government leader can go home and say they have agreed on an inequitable solution, we need to find a way of taking all our circumstances into account."