An emotional video of a Maori haka performed at a New Zealand wedding has gone viral, getting more than 20 million views on Facebook.

Bride Aaliyah Armstrong was moved to tears as she watched their friends and family do the ceremonial war dance at her wedding reception.

She and groom Benjamin Armstrong, who are of Maori, European and Samoan descent, joined in.

They hugged their friends and family at the end of the haka.

The video, created by the bride's cousins, went viral after it was posted on the 'I'm proud to be Tongan' Facebook pageon Thursday (Jan 21). The post had close to 200,000 'likes'.

It was widely reported by the media in New Zealand, Australia and Britain.

Mr Armstrong told the Daily Mail Australia: "The name of the haka is Tika Tonu. The best man asked all those that knew it to come up and gather together...from there my older brother - Joel Armstrong, who led the haka - told them how they would start."

Hakas are known around the world thanks to the New Zealand All Blacks rugby team that does the routine before their games, to intimidate their opponents.

It is a rhythmic chant often accompanied by exaggerated facial expressions, forceful movements and feet stamping.

It is also used to welcome distinguished guests, and at special occasions such as weddings and funerals.

One was performed at rugby great Jonah Lomu's funeral in November 2015.