Now is the time to fill up the car, AA advises

The Automobile Association says now is the time to fill up the car, as renewed fighting in the Middle East is expected to push up petrol and diesel prices.

The United States escalated attacks after Iran said it had closed the Strait of Hormuz.

AA fuel spokesperson Terry Collins said prices would probably rise more slowly than when the conflict began because more tankers can use other shipping routes.

But people should fill up now if they could afford to, Collins said.

"Last week was even better. This week is still good. Next week's going to be worse.

"The longer you wait, the more you're probably going to have to pay."

Some fuel companies had already skipped their usual Tuesday specials this week, Collins said.

"That's another strong indicator that prices are going to move up, they're not in a hurry to get rid of ... their cheaper product."

Collins said fuel arriving in New Zealand would immediately attract higher prices because importers would otherwise face a financial shortfall on their next shipment.

"If I've got $100,000 worth of fuel in my tank, and next week it's going to cost me $120,000 to fill it up when it needs filling, I'm going to charge $120,000 for that fuel I've got in my tank now, because otherwise I'm going to have a shortfall of $20,000 when I go to buy my fuel next week," he said.

Collins said petrol prices would probably not be significantly more than $3/litre again, and diesel prices would likely see a bigger rise than petrol.

He believed the government had done a good job of managing the fuel crisis.

"We don't have a supply problem. We just have a price problem, and that's a global thing," he said.

"We're just at the mercy of what happens overseas, being a small country at the end of the world."

The government's weekly fuel relief payment for low income families will continue until the average price of 91 petrol stays under $3/litre for four consecutive weeks.