Wellington: New Zealand rugby legend Jonah Lomu, who revolutionised wing play to become the sport's first global superstar, died on Wednesday in Auckland at the age of 40, prompting a global outpouring of grief.

Lomu had suffered from kidney disease for two decades and had a transplant in 2004 but former All Blacks doctor John Mayhew said his death was a complete shock.

"It was totally unexpected," Mayhew said. "Jonah and his family arrived back from the United Kingdom last night and he suddenly died this morning."

Lomu, who was awaiting another transplant and undergoing dialysis treatment, had undertaken commercial obligations at the recent Rugby World Cup in England, won by New Zealand.

His death took the rugby-mad country by surprise and triggered a flood of messages of condolence from around the world. New Zealand's parliament expressed their sorrow before they began proceedings on Wednesday.

"Anyone who was living in New Zealand in the 1990s would not have failed to notice the massive impact Jonah Lomu had not only on sports fans but the wider community in this country," sports minister Jonathan Coleman said.

"He was a man who came from humble beginnings in Mangere, South Auckland and rose to become rugby's first global superstar."

World Rugby chairman Bernard Lapasset led the international tributes: "Jonah's contribution to rugby cannot be overstated," he said in a statement. "He was the first superstar player and, through his sheer brilliance and love of the game, he brought much joy to the rugby family and took our sport to a new level of profile."

Lomu's record of 37 tries in 63 tests was an impressive haul, all the more so considering he played much of his career with nephritic syndrome, the disease that attacked his kidneys.

New Zealand Rugby, who arguably owe part of their huge commercial success over the last 20 years to Lomu's performances at the 1995 World Cup, said they were "shocked and saddened" by Lomu's death.

"We're lost for words and our heartfelt sympathies go out to Jonah's family," chief executive Steve Tew said. "Jonah was a legend of our game and loved by his many fans both here and around the world."

"Jonah Lomu was a player who changed the face of modern rugby," the International Olympic Committee president Thomas Bach said.

"He was an icon not just for New Zealand fans but for all rugby fans around the world. It is sad that he did not live to see the sport return to the Olympics Games next year in Rio de Janeiro."