Whanganui Mayor Hamish McDouall has labelled as "just extraordinary" Whanganui's part in the iconic Ganges River in India being accorded the rights of a human being.
An Indian court ordered on Monday that the Ganges and its main tributary, the Yamuna, be accorded the status of living human entities.
The judges heralded legilslation passed in New Zealand last week that extends human rights to the Whanganui River as the inspiration for the decision.
The Ganges river is considered sacred by more than a billion Indians and is the first non-human entity in India to be granted the same legal rights as people.
The decision means that polluting or damaging the rivers will be legally equivalent to harming a person, Britain's Guardian newspaper reported.
Mr McDouall welcomed the development describing the Whanganui River legislation as world-leading. "What were seeing is a significant step in enhancing the environment in which we live."
"It's incredibly exciting," he said of the Indian decision. "It's a re-inforcement of the status of the Whanganui river as a legal entity. We should formally write to the Ganges and congratulate it," he joked.
Mr McDouall said it was "amazing" to have the Ganges and the Whanganui rivers linked.
"There's a very deep-centred connection from the people to the rivers both here and in India. We wait with baited breath to see when the Nile and Yangtze catch up."
Mr McDouall, a lawyer, said he was eager to read the High Court decision.
He recalled reading the writings of a philosopher who wrote some 40 years ago of the intrinsic rights of natural features to have rights and to have them respected and observed.
"Everyone poo-hooed him at the time. Natural features can not themselves take anyone to court - but now they have the right not to be polluted, and in essence to be consulted."
Judges Rajeev Sharma and Alok Singh said the Ganges and Yamuna rivers and their tributaries would be "legal and living entities having the status of a legal person with all corresponding rights, duties and liabilities.
"All of this will (take) immediate effect, but you can't stop the discharge immediately. So how this decision pans out in terms of practical reality is very unclear."
Length: 290 km
Claim: Third largest river in New Zealand
Sacred to: Maori
Where: New Zealand
Length: 2,525 km
Claim: Third largest river in the world
Sacred to: Hindus
Where: India and Bangladesh