Key Points:

The Progressives' sole MP Jim Anderton says he will remain in coalition with Labour - even in opposition.

The Wigram MP announced his unorthodox position today.

Mr Anderton is a former Labour MP and spent the last nine years in a government coalition with Labour - first as an Alliance MP and then as a Progressive Party MP.

Mr Anderton differentiated himself from Labour on few issues - leading several commentators to suggest he had all but rejoined the party he split from in the 1980s.

Mr Anderton today said he was sticking with Labour in opposition and would be the "opposition coalition's" agriculture spokesman.

"Progressives share with Labour a joint determination to ensure that National govern for no more than a single term, to stop it before it can do lasting damage to New Zealand and to refresh New Zealand's interest in a progressive future.

"Our leadership group has met and we believe our long-term future is with our close partners in the Labour Party."

A priority for the Progressives, beyond his coalition role, would be to push better access to dental care, Mr Anderton said.