National's popularity has taken a dip, a new poll shows.

The One News Colmar Brunton poll, the first major one since the May 20 Budget, showed support for the National Party had dropped five percentage points to 49%, but remained well clear of Labour, which was stagnant on 33% support.

The poll showed the Greens had climbed to 7% support and the Maori Party to nearly 4% . ACT remained less than 2%.

In the preferred prime minister stakes, Labour leader Phil Goff had only 6%of the vote, 40 percentage points behind National leader and Prime Minister John Key.