Candlelit memorial in for British politician Jo Cox

British MP Jo Cox had previously worked for Oxfam International. Photo / AP

As Brexit hangs in the balance a New Zealand politician has penned a poignant tribute to his slain friend Jo Cox on the day she would have celebrated her 42nd birthday.

Labour's Phil Twyford revealed a group of current and former Oxfam staff gathered on Auckland's waterfront this week to hold a small candlelit memorial for the British politician killed outside her office by a disgruntled constituent last week.

He said the politician, who only a day before her death was campaigning for the UK to stay in the European Union, was a delight and irrepressible but deadly serious about making a difference in the world.

She had previously worked for Oxfam International, was passionate about humanitarian issues and lived life to organise a better future for the world.

He said her charm and persuasiveness made her a formidable lobbyist dealing with the EU trade mandarins and she was skilled at navigating non-government organisation politics.

"We don't need to canonise Jo. She was like us. She was one of us. And if the terrible events of last week hadn't happened, today would have been for her like any other day in our lives: juggling a partner and two young kids with the demands of life as a politician, and somehow trying to fit in her birthday celebration."

He said one of the reasons his friend's killing had been so shocking was that she was an elected member of Parliament, selected by her local community to serve them.

Labour MP Phil Twyford said the way Jo Cox lived her life and practised her politics left clear guidance on how she should best be remembered. Photo / George Novak

"She was going about her work. Having just done a constituent advice clinic, she was attacked on the street.

"We won't know until the trial is complete exactly why her killer targeted Jo. But it seems clear from the little we know already that she was targeted because she was a politician. The attack on Jo was an attack on our democracy, and our cherished democratic rights."

Mr Twyford said it should sound a caution to all those who denigrate the democratic process and demonise our elected representatives.

He said the way that Ms Cox lived her life and practised her politics left clear guidance on how she should best be remembered.

It included standing in solidarity with those who were suffering and showing compassion in trying to bring about improvements.