Petrol price hike not justified, but 'nothing we can do'

The Automobile Association (AA) says fuel companies are to blame for the latest fuel price hike - but there's nothing we can do about it.

"We're at the mercy of the markets really unfortunately," AA spokesperson Mark Stockdale told The AM Show.

"We've been hit by a double-whammy. The exchange rate fell a couple of weeks ago following the election announcement and then more importantly the international commodity prices have risen.

"The increase we saw on Tuesday - a 3 cent increase on petrol and diesel - the AA's view is that that increase was not justified.

"We couldn't see that was linked to a recent change in the commodity price or the exchange rate so that's one for the fuel companies to say why."

Petrol prices have hit a three-year high, with the weekly average retail price in Auckland, Hamilton, Wellington and Christchurch sitting at $2.129 - signifying a rise of 9 cents a litre in just eight days.

The highest main port price ever was $2.269 in 2013, according to the AA.

Mr Stockdale says that's concerning.

"But look, it doesn't really matter, there's not a lot that we can do… But we've seen prices go up 10 cents in the last fortnight.

"In saying that there are lots of parts of New Zealand that are still below that $2.30… So it just depends on where you live."

BP and Z Energy have both credited the exchange rate and commodity prices as the rationale behind their decision, with the former saying it is simply responding to the barrel price rising to its highest point in two years.

"When the New Zealand dollar is weaker against the US it costs us more Kiwi dollars to buy the same volume. So there is a double impact here - steadily rising international crude oil and refined fuel prices and a weaker NZ dollar both putting upward pressure on prices."

Gull has bucked the trend somewhat, announcing on Tuesday that it wouldn't follow the other fuel giants by increasing its petrol prices for a third time in the last week.