Donald did not die of heart attack 

Greens co-leader Jeanette Fitzsimons reflects on Rod Donald's life and achievements. Marty Melville / Getty Images

The hurly-burly of parliamentary business has been postponed until next week so MPs can attend the funeral of Greens co-leader Rod Donald in Christchurch on Thursday morning, but the cause of his death is now a mystery.

Mr Donald, a seemingly fit 48-year-old, died suddenly in the early hours of Sunday at his Christchurch home.

His partner, Nicola Shirlaw, and one of their daughters attempted to revive him with CPR.

He was suspected of having had a heart attack but autopsy results that came through last night have ruled this out.

Further tests will be conducted to try to establish the cause of death, a Greens spokesperson said.

There had been no history of heart trouble in Mr Donald's family.

Mr Donald's service will be in the Christchurch Cathedral and a private burial will follow.

Thursday afternoon was to have been the first question time of the new Parliament, and one that was expected to be highly politically charged over controversial support arrangements negotiated by the minority Labour Government.

The Greens resented being sidelined from coalition at the insistence of New Zealand First and United Future, the leaders of which are now ministers but who insist they are not part of the Government.

Mr Donald's five Green colleagues and other MPs will now be able to attend his funeral without having to hurry back to Wellington to switch from an atmosphere of collegial respect to warfare.

Prime Minister Helen Clark is expected to attend the funeral with a large turnout of Labour MPs.

National deputy Gerry Brownlee thought about half of the National caucus would be at the Christchurch Cathedral to farewell Mr Donald, an MP since 1996.

United Future leader Peter Dunne, famously purple in his criticism of the Greens, is thought to be taking soundings as to whether his attendance would cause offence.

It is not known whether New Zealand First leader Winston Peters, the subject of Mr Donald's most scathing political attacks, is planning to attend.

All four Maori Party MPs will attend. They joined Green MPs in Mr Donald's office yesterday morning to pay their respects before the swearing in of MPs in the afternoon.

Brief tributes were paid to Mr Donald yesterday during parts of the swearing-in.

But fuller remarks will be made tomorrow, when Parliament is scheduled to pay formal tribute to former Labour Prime Minister David Lange.

The House is to rise tomorrow as a mark of respect for Mr Lange and was to have resumed on Thursday for question time.

It will now resume next Tuesday at 2pm for the first question time.

Co-leader Jeanette Fitzsimons said afterwards that the respect shown to Mr Donald from other parties was heartening.

She said the Greens also wanted to arrange a service in Wellington, perhaps at the end of next week.

She said co-leaders were elected at party conferences in June and there was no urgency to name Mr Donald's replacement, which was a big decision that needed to be taken carefully.

"It's not automatic that it would need to be someone that's in Parliament."

Asked whether the constitutional requirement to have a man and woman as co-leaders might disadvantage talented women in the party, she said the rule was "not just about equity".

"It's also about representation and completeness."

She said it was quite hard to talk about the issue of succession "when Rod isn't even buried yet".

Former MP Nandor Tanczos is the next person on the Greens party list and Ms Fitzsimons said he was in shock and had been given time to think about returning to Parliament.

"It's a horrible, horrible situation to mourn a close friend and take their place so I've just said 'take your time'."

Yesterday

* A heart attack has been ruled out as the cause of death of Greens co-leader Rod Donald, 48, who died suddenly in the early hours of Sunday.

* Five mourning Green MPs yesterday placed a photograph of their colleague on his possum-skin-covered seat in Parliament.

* In the House, MPs laid flowers on what would have been his desk.

* The Maori Party's four MPs swore allegiance to the Treaty of Waitangi as well as to the Queen when Parliament opened - but had to repeat their vows without a Treaty oath.

* Leader of the House Michael Cullen delayed the first question-time to next Tuesday so MPs can attend Mr Donald's funeral in Christchurch on Thursday.