Central Christchurch came to a standstill today for the funeral of Green Party co-leader Rod Donald.

Mr Donald, 48, died suddenly at his Christchurch home early last Sunday morning.

Parliament was suspended today to allow MPs to attend Mr Donald's funeral service in Christchurch Cathedral, which was one of the biggest funerals seen in the city in many years and was as close to a state funeral as could be possible without actually being one.

Inside the cathedral it was standing room only, with about 700 mourners packing every available space.

Outside, 500 or 600 others gathered by the main doors listening quietly to the many moving eulogies.

Mr Donald's simple unvarnished wooden casket was borne to Cathedral Square in a bus with his partner Nicola Shirlaw, daughters Holly, 21, Emma, 18, and Zoe, 13, and Mr Donald's parents, Joyce and David Donald.

They were accompanied from Mr Donald's Green Party electorate headquarters in Bedford Row by a large group of cyclists.

The bus signified Mr Donald's passionate support for public transport facilities and the cyclists honoured his own favourite form of personal transport.

The funeral service itself was a mixture of remembrance, poignancy, humour and a celebration of his life, together with dance and music.

Christchurch Cathedral Dean Peter Beck told mourners it was the first time the rock group Pink Floyd, one of Mr Donald's favourite bands, had been played in the cathedral.

Mr Beck said there was no more appropriate a place to farewell the environmental crusader touted as one of life's truly nice guys and one of Christchurch's favourite sons.

"Rod, this is all too soon, mate," Mr Beck said. "This shouldn't be happening."

Mr Donald, he said, had been a regular visitor to the cathedral and had celebrated a number of events there, "promoting justice and love and truth and beauty".

Central to the church was its theme that nothing is stronger than love, Mr Beck said.

"Rod believed that and followed that doctrine throughout his life."

Prime Minister Helen Clark said Mr Donald's death was a "deep shock to all of us" and a reminder of life's fragility.

Mr Donald, she said, had packed more into his "48 short years" than most people could hope to achieve even into their 90s.

Australian Green Party leader Senator Bob Brown said Mr Donald had a big influence on his party and was "a truly global Green".

"You have wonderfully weighted the scales in favour of compassion for humanity and security for our wild and beautiful planet," he said.

A Zimbabwean interdenominational group paid tribute to Mr Donald's support for ethnic minorities through song and dance. He was, they said, their hero.

At the conclusion of the service, Mr Donald's casket, adorned with an arrangement of flax flowers was carried from the cathedral as a peal of bells rang out across the square.

His casket was carried through the throng to nearby Warners Hotel, an old watering hole of Mr Donald's, where it rested in the garden bar while mourners filed past to pay their respects.

Mr Donald was later taken for a private family burial.