The relaunch began with a small ceremony at Cowra's World Peace Bell.

Chair of the Australian Chapter of the World Peace Bell, Ian Brown, paid tribute to the victims of the Christchurch Mosque terrorist attack, noting the simultaneous ringing of the bells in Cowra and Christchurch on World Peace Day this year.

"The ties that bind our countries are forever enduring. We are democratic nations, the closest of neighbours," Mr Brown said.

"We stand together with the people of NZ to promote peace and unity in our communities."

New Zealand High Commissioner, Dame Annette King also read out a poem, "The Christchurch Response" before Maori elder Issac Cotter and his wife Trish shared with a prayer with the audience.

An official dinner was held on Friday night, which featured a special video message from New Zealand Prime Minister, Jacinda Ardern and Member for Wairarapa, Kieran McAnulty MP who represents Cowra's sister city, Featherston.

Ms Ardern said she was looking forward to the festival.

"I'd like to thank the Cowra community, in particular Mayor Bill West for inviting the NZ High Commission to play a part as guest nation for the Cowra Festival," she said.

"I'd also like to thank all the 2020 Youth Ambassadors for their contribution too.

"We're looking forward to contributing to the festival in a variety of ways."

Mr McAnulty said the two nations and towns had a long standing relationship.

"If it's not our Anzac history, our sporting history or through economic ties, we're as close as you can possibly get," he said.

"It's those strong connections that we really value, we're keen to continue those through the Cowra Festival of International Understanding next year."

The Festival's traditional tree planting took place on Saturday morning, with the High Commissioner thanking Cowra for their warm welcome.

"We have been surrounded by interesting people, good conversation, wonderful food and a welcome we will remember for a long time," she said.

"It is a special occasion and it does signify the relationship between Australia and New Zealand, Cowra and New Zealand, Cowra and Featherstone.

"When we say, we are cousins, we are, we've all got relatives in each other's countries, we've joined together."

Mayor West said the tree, a Toothed Lancewood, would be a constant reminder of the two nation's cultures and history.

"It will cause us to be able to reflect. The tree will grow, our relationship will grow too," he said.

"Having New Zealand as a guest nation is very important to us, our friends, our close relatives, we have so much in common and we share so much."