New Zealand's Ardern forms government with Greens

Having delivered the biggest election victory her center-left Labour Party has seen in half a century, she no longer needs the support of other parties to govern.

However, coalitions are the norm in the nation of nearly five million people, as parties look to build consensus.

The Greens are obliged to back the government over decisions made in their portfolios but are otherwise entitled to take a different position to Labour.

Prior to the October election, the Labour Party was in a governing coalition also with the Greens and New Zealand First.