Yes, as a member of the United Nation Framework Convention of Climate Change, New Zealand signed the Kyoto Protocol on May 22, 1998. It ratified the Kyoto protocol, four years later, on December 19, 2002.
As per its ratification agreement, New Zealand is required to maintain its emission levels same as that of the 1990’s level. It does not have to reduce, but it is not permitted to increase the levels of emission. For excess emission, New Zealand would be required to take responsibility.