It is quite plausible that former Opposition leader David Shearer could be Foreign Minister at a time that New Zealand is sitting on the UN Security Council.

That's one possible reason for his agreement to help the Government campaign for the seat in New York next week. Another is that he knows first-hand how the power of the Security Council can affect people's lives.

Mr Shearer was working in Rwanda the last time New Zealand sat on the Security Council, trying to reunite thousands of children who had become separated from their parents in the midst of genocidal slaughter that claimed up to one million lives.

He remembers New Zealand leading the debate on what the international response should be.

"On the ground in Rwanda people recognised New Zealand's contribution and I was immensely proud to be on the business end of what was going on and having New Zealand saying the right things and standing up for the right things in New York."

Labour's foreign affairs spokesman will next week call on former work colleagues at the UN. Having worked during various crises in Iraq, Jordan, Israel, the Palestinian territories, Somalia, Sierra Leone, Liberia, and Rwanda, he will also call on several permanent representatives to press New Zealand's case, as well as small island states.

"New Zealand being on the Security Council is a very big deal," he said. " It's the possibility of having New Zealand values and New Zealand's sense of fair play being able to be projected on a world stage, and sitting down with the big players and having an equal voice with them."

Council bids have a long gestation. In 2004, former PM Helen Clark launched New Zealand's bid for the vote in 2014, likely to be in mid-October, for a seat in 2015 and 2016.

Others standing are Spain and Turkey.

Mr Shearer said the visit next week arose from an invitation by Foreign Minister Murray McCully and both believed it should remain a bipartisan bid.