Twin giraffe calves have been born at Auckland Zoo, though sadly one had to be put down.

Auckland Zoo welcomed giraffe twin calves on New Year's Eve. Source: Supplied

The twins were born to seven-year-old mother Kiraka in an "extremely rare" event on Saturday morning.

Only about 30 cases of giraffe twins have been reported worldwide, Auckland Zoo said.

Twin giraffe calves were born at Auckland Zoo on New Year's Eve morning, unfortunately only one calf survived. Source: Supplied

The zoo announced the birth with "great joy and sadness" as the giraffes were born premature and although the female calf was able to start suckling, the male was very weak and unable to form a bond with Kiraka.

"Despite great efforts of all involved, the male's post-birth complications became untreatable and we took the very difficult decision on welfare grounds to euthanise the young male calf yesterday morning," said curator of mammals Warren Spencer.