National is ruling out a referendum on co-governance, for now.

Act is making the referendum a bottom-line in any coalition negotiations after next year's election.

National leader Christopher Luxon told Kate Hawkesby it's not something the party is considering right now.

He says it's not the party's policy and he doesn't see the need.

Prime Minister Jacinda Ardern says it's up to National to make its position clear.

LISTEN ABOVE

• Heather du Plessis-Allan: If I was in the Labour Party, I'd get out ASAP
• Splash the cash: Private Three Waters consultants paid $16m