A white horse will be gifted to Tōshōgū Shrine in Nikkō, Japan to replace the one which had been there until it died last year.
Foreign Affairs Minister Winston Peters said it was a tradition of over 50 years.
A New Zealand white horse had been a feature of the Tōshōgū Shrine since 1964. The shrine is 150km north of Tokyo.
The shrine is one of the most famous buildings in Japan. It was built by the Tokugawa Shōguns and is a world heritage site with almost two million visitors flocking to see it each year.
Mr Peters made the announcement at a ceremony at the shrine today when he presented a framed photo of the replacement horse to the shrine's chief priest, Hisao Inaba. The white horse would be shipped to Japan later this year.
"The horse is to be named Kōmaru. He is a gift of friendship from the people of New Zealand to the people of Japan and a symbol of the enduring relationship between our two countries," Peters said.
Kōmaru, a white 10-year-old purebred Andalusian gelding, will replace the previous New Zealand white horse, Kōtuku, which passed away in 2017.
"Kōmaru in the Māori language means 'sheltered'. Our hope is that Kōmaru will enjoy a long and protected life as a sacred member of the Tōshōgū Shrine," Peters said.
It will be the fifth New Zealand white horse gifted to the shrine as a symbol of friendship between New Zealand and Japan.
The first was gifted after the 1964 Tokyo Olympics, to the Japan Equestrian Association, which transferred him to the Nikko Tōshōgū Shrine.
When he died in 1976, a second white horse, Marutai, was gifted to the Shrine. Marutai suffered a premature death in 1980, and the third horse, Koha, was presented by then Prime Minister Robert Muldoon in 1981. The fourth horse, Kōtuku, was given to the shrine in 2005 by former Prime Minister Helen Clark.
Kōmaru will live in a spacious stable at the shrine, where thousands of visitors each day can see him.
Peters visited the shrine as part of a three-day visit to Japan for bilateral talks and to attend the eighth Japan-Pacific Leaders' meeting. He is due to leave Tokyo tonight.
"This visit reaffirmed the strength and significant mutual benefit of the New Zealand Japan relationship," he said.
"New Zealand and Japan continue to enjoy a strong trade and economic relationship, which will continue to grow following the conclusion of the Comprehensive and Progressive Trans Pacific Partnership Agreement.
"We have also long enjoyed friendships through cultural and sporting contacts. And we have shared interests on defence and security, including on issues like North Korea."
Peters' programme also included and a formal meeting with Prime Minister Shinzo Abe and meetings with Deputy Prime Minister and Minister of Finance, Taro Aso, and with Foreign Minister Taro Kono.
"My meetings with Japan's senior political leadership confirmed there is much that New Zealand and Japan can do together to harness even more value from the relationship".
"Our shared commitment to the rules-based international system makes Japan an important partner for New Zealand in the Asia-Pacific."