UPDATED 4.55pm: Former Labour leader David Cunliffe is not seeking re-election.

Current leader Andrew Little says David Cunliffe is retiring to pursue a management consulting career outside politics.

Though it appears National MP Judith Collins won't be missing his presence.

When asked if she still considers him a moron, her answer was "yeah, pretty close, yeah."

However Green Party Co-Leader Metiria Turei has a more positive view of the Labour MP.

She enjoyed working with him when he was Labour leader and understands that former Green Party Co-Leader Russel Norman did too.

John Key said the announcement was reasonably predictable and Cunliffe was clearly not wanted by Labour's current leadership.

"He's a talented guy so he wouldn't want to sit around here with nothing to do."

The Labour Party is going to have to find itself a new candidate for the Auckland seat of New Lynn.

The seat Cunliffe held with a more than 4,500 vote majority in 2014, and on the face of it a safe Labour seat, will be up for grabs.

However the seat may not be as solid as it appears for Labour, for while Mr Cunliffe held the seat comfortably in the years he had it, the National Party has won the party vote in New Lynn at the last two general elections.

Cunliffe was elected to the leadership of the Labour Party ahead of the 2014 general election, taking the job from David Shearer.

It followed a period of factional infighting, in which some in Labour said he undermined Mr Shearer.

Labour’s 2014 campaign wasn’t successful, and Cunliffe relinquished the job to Andrew Little.

Otago University politics lecturer Dr Bryce Edwards said under different circumstances Cunliffe might have shone more brightly.

But that election was a difficult battleground, with all the craziness of Kim Dotcom, the Internet Party and Dirty Politics.

Dr Edwards thinks Cunliffe will always question whether he would have been more successful if he hadn't gone for the leadership when he did.

In the previous Helen Clark led Labour Government, Cunliffe served as Minister of Health and Minister of Communications and Information Technology.

He has been a member of Parliament since 1999, when he was elected in Titirangi. When that constituency was abolished, he was elected as the MP for New Lynn, a seat he has held ever since.