The new mayors of Auckland and Christchurch have teamed up to create a new Three Waters proposal.

The main difference is the regional water organisations would be owned and governed by councils, not a co-governance body.

Finance Minister and Deputy Prime Minister Grant Robertson explained his thoughts on the plan.

"From what I have read, it does sound like it might not quite reach what we need in terms of aggregation. They're talking about an opt-in situation, which might not mean that we get the heft into the entities that they need."

LISTEN ABOVE

• Alternative plan for Three Waters Reform being discussed
• Auckland and Christchurch mayors put forward alternative plan for Three Waters
• Christchurch mayor discusses alternative solution for Three Waters Reforms