Prime Minister John Key is to visit China this month to discuss upgrading the free trade agreement between the two countries that was signed almost eight years ago.
But he is warning against expecting a swift resolution.
"We are going to work hard on it. I can't guarantee immediate progress," he said of the upgrade that should automatically follow the signing of an FTA between China and Australia, which is understood to have included more favourable terms than New Zealand's deal.
Under the NZ-China FTA's "most favoured nation" clause, any improved access for another signatory is by rights extended to the other signatories.
Asked whether China acknowledged New Zealand's MFN claim, Key said: "I think so."