Andrew Little has stood down as Labour leader

Labour leader Andrew Little has stood down as Labour leader - leaving the way clear for his deputy Jacinda Ardern to take up the role.

Little made the announcement after a brief meeting this morning where there was speculation he would face a challenge for the job.

Sspeaking to the Herald an hour before his announcement, Little had refused to comment on whether he would resign, but said he was not expecting to face a confidence vote and was not expecting to be challenged.

It follows two days of turmoil after a string of bad polls and Little's admission he had asked senior colleagues if he should step down.

Some in Labour were understood to have put together the alternative leadership team of Jacinda Ardern and Kelvin Davis to replace him if he decided to go - but other senior MPs said they did not expect that to be actioned unless Little went of his own volition.

Although there was speculation others might challenge for the role, many MPs were of the view that if there was to be a change Ardern was the only option.

In advance of the development, MPs were mixed on the merits of a leadership change so close to the election. Stuart Nash said he believed Labour would be "doomed" if it changed leaders at this point, but others said it could help hold up Labour's vote from further collapse.

Little was elected leader in 2014 after Labour's election result of 25 per cent. Although he had little caucus support at that point, he had strong support from the unions affiliated to Labour and was credited with calming Labour's notoriously divided caucus.

Andrew Little's full statement

Today I have announced that I will step down as leader of the Labour Party.

I'm proud to have been leader of the Labour Party, and have given this position my absolute and unwavering dedication, just as I have done so for more than 25 years in the Labour movement.

While obviously this is a sad decision, I have been privileged to have led a united, talented team of Labour MPs, proud to have progressed the values and issues that New Zealanders care about and proud to stand with working New Zealanders.

I remain committed to the Labour cause of putting people first, lifting the rights of working New Zealanders and strengthening Kiwi families.

The Labour team of MPs and staff have worked incredibly hard during my leadership, however recent poll results have been disappointing.

As leader, I must take responsibility for these results. I do take responsibility and believe that Labour must have an opportunity to perform better under new leadership through to the election.

I am determined to make sure that Labour fights this campaign with the greatest of resolve, because far too much is at stake for far too many New Zealanders.

New Zealand needs a Labour-led Government, and in order to achieve this Labour must fight without questions over its leadership.

The campaign is on a good footing, Labour's caucus is united and the party is healthy.

My colleagues in the Labour Party caucus will elect a new leadership team this morning. I wish my successor all the very best in their new role, and offer my wholehearted support to them.