National, ACT struggle over co-governance

The battle lines have been drawn in an ideological struggle between National and the ACT Party, ahead of any potential coalition arrangements.
ACT wants to put the Treaty of Waitangi to a public and binding referendum and says it would be a bottom line in any governing negotiations.
National is so far shying away from the 'rule in, rule out' game, but would be likely to need ACT if it's to form a Government next year.
Political reporter Anneke Smith has more.