An American naval ship will enter New Zealand waters next month, for the first time in more than 30 years.
The USS Sampson will take part in the New Zealand Navy 75th anniversary celebrations next month.
Prime Minister John Key said he was satisfied the military ship was not nuclear armed or powered after considering official advice.
The US has not sent a naval ship to this country since 1983, as it refuses to say whether its ships are nuclear-armed, as required by New Zealand's nuclear-free law.
Mr Key said the process for considering the visit was the same as that used for all ships attending the International Naval Review.
"New Zealand's legislation also does not allow ships which are nuclear propelled into New Zealand and the advice I received from officials is that the USS Sampson is not nuclear powered.
"New Zealand looks forward to the USS Sampson's participation in the International Naval Review to mark the Royal New Zealand Navy's 75th anniversary. The visit is a further reflection of the depth of the bilateral relationship with the United States," Mr Key said.
The International Naval Review is being held in Auckland on 17-22 November.