The Automobile Association is calling on petrol companies to drop fuel prices by up to five cents a litre by Monday.
AA policy analyst Mark Stockdale said the Singapore benchmark price, coupled with the exchange rate has given petrol companies enough of a margin to pass on savings
to motorists.
However petrol companies do not agree.
Gull general manager Dave Bodger said he is optimistic of a drop but not just yet.
"We had a look yesterday, there wasn't that chance there but we're looking two or three times a day at this point in time to see if we can do something," said Bodger.
He said he did not have the figures in front of him so could not say if diesel had come down overnight.
Bodger said if prices continue to fall then the savings will be passed on.
"It's good of Mr Stockdale to know our business," he said.
BP spokeswoman Diana Stretch said it would be a "hell of a stretch" for fuel prices to drop.
She said the international price of refined petrol had decreased by just over 70 New Zealand cents a litre since July, while pump prices had decreased by 79 cents and when the GST is taken out - that translates to a 70 cent drop.
"That shows the decrease is clearly passed on," Stretch said.
But Stockdale said the prices coming out of Singapore are low enough to justify a price decrease of between four and five cents by Monday.
"Particularly diesel, there has actually been a drop in the refined price. There hasn't been a drop in petrol but the margins were comfortable anyway, they were at the high end of the range," Mr Stockdale said.
He said petrol companies should respond to Reserve Bank Governor Alan Bollard who called on petrol companies, amongst others, to drop prices further and "play their part" yesterday.
Stockdale said the New Zealand dollar has increased petrol companies" margins by strengthening slightly. Petrol companies buy fuel in US dollars and the Kiwi has strengthened since the last drop in petrol.
