A group of Whanganui activists will travel to Auckland next month to protest a visit by a United States' warship.
The warship, along with those from 17 other countries, has been invited to come to New Zealand for the 75th anniversary of the New Zealand Navy.
Around 16 members of Peace Action Whanganui (PAW) will travel to Auckland to take part in the protest on November 15, spokesperson Chris Cresswell said.
"In 1984, New Zealand proudly banned nuclear powered or armed warships from our waters. The United States has consistently refused to confirm or deny whether their ships are nuclear armed or powered and so its warships have been prohibited from our waters."
Mr Cresswell said the New Zealand government had said it was using a source other than the United States government to confirm that the visiting warship was not nuclear powered or armed.
"Members of Peace Action Whanganui believe this is against the intent and spirit of New Zealand's nuclear ban," he said.
Peace Action Whanganui's protest will also target a major international arms manufacturers' and dealers' conference, to be held in Auckland to coincide with the Navy's anniversary.
"PAW members believe New Zealand should not be supporting the international war machine this way," Mr Cresswell said.
"PAW members will be taking part in a blockade of the arms conference and several members will be taking to the waters in canoes and kayaks in attempt to obstruct the warships."