Both the National and Labour Party leaders say they believe oil companies are acting ethically over prices.
US crude has fallen on the world markets to about half of July's record highs, which has prompted calls for that to be mirrored at the pump.
On Friday 17 October Shell cut petrol prices by 8 cents a litre, and diesel by 6 cents, with all its competitors following suit a short time later.
That put the price of unleaded at BP, Shell, Caltex and Mobil stations at $1:81.9c, and at Gull stations at $1:80.9.
National leader John Key encouraged oil companies to act as quickly as possible.
"There obviously is a bit of lag and there are a number of factors that go into those petrol prices but obviously encouraging those oil companies to move as quickly as they can is important."
He says he believes companies in New Zealand are acting ethically, but would like to see some more price reductions.
Labour leader Helen Clark pointed to external factors which prevented the price falling back to last year's levels.
"I'm told there would be a couple of slightly different factors between last year and this year, for example around the sulphur parameters and the fuel mix, around the cost of freight..."
Earlier this year the Government looked at but rejected the appointment of a petrol commissioner to monitor prices.