Petrol and diesel rose 3c a litre yesterday. Petrol in the main centres yesterday cost $1.779 a litre for 91 octane, $1.829 a litre for 95 octane, and $1.339 a litre for diesel.
Prices were higher in inland Otago.
BP spokeswoman Diana Stretch said the previous high was $1.769 in August 2006.
Prices at the pump were driven by international crude oil prices, and oil hit a record high of more than $US110 ($NZ135) a barrel on Wednesday. It steadied near $US110 yesterday.
If the New Zealand dollar dropped to 60c against the US dollar then prices would be more than $2 a litre, she said. The dollar hovered above 80c yesterday.
Diesel prices had risen 13c a litre in the past couple of weeks because of international demand during the northern hemisphere winter, she said.
AA spokesman Mark Stockdale said the New Zealand dollar had dropped a couple of cents earlier in the week, leaving companies with little option but to increase prices.
But he said the price might not reflect the true fundamental situation of the supply and demand for fuel, and was being driven by speculation.
International investors have rushed into commodities during the past month to hedge against inflation and the softening US dollar, despite concerns over a recession in the US and rising fuel inventories.
The US dollar dropped to a 12-year low against the yen and a record low versus the euro yesterday, amid uncertainty about the long-term impact of the US Federal Reserve's efforts to ease strained credit and money markets.
AA motoring affairs director Mike Noon noted on Wednesday that the price of 91 octane in New Zealand was 34c a litre less this time last year.
Based on the latest price, a 50-litre tank would cost $17 more to fill this year.
‘‘We don't speculate on forward prices but prices are volatile and there seems to be no respite for motorists in sight,' Mr Noon said.
