Key Points:

Today's six cent price rise in petrol prices is justified, according to the Automobile Association.

All four major petrol companies increased their petrol prices by six cents a litre this morning.

AA policy analyst Mark Stockdale said there had been a rise in refined petrol of about six cents a litre in the last two days.

"It's been a quick reaction so if there is any recovery, AA will keep an eye out to ensure they drop it just as quickly," Mr Stockdale said.

Shell, Caltex, Mobil and BP have all increased their petrol prices by six cents and are now charging 171.9 cents a litre for 91 unleaded.

Gull's retail business manager Graham Stirk said its prices would not be going up today but the company would review its prices again tomorrow.

BP spokesman Neil Green said the cost of refined petrol on the overseas markets has increased by 14 cents a litre in the past week.

He said that meant that BP had absorbed an eight cent rise.

Mr Green said the weaker New Zealand dollar had also had a part to play.

Shell spokeswoman Kylie Reeves said the increase in price was due to a jump in the price of refined petrol on the Singapore market.

She said the international price of petrol had gone up by nine per cent in the past week.

"We tried to hold off. We review it each day and unfortunately it looks like we had to put it up today," Ms Reeves said.

Caltex spokeswoman Sharon Buckland said the price rise was also due to a rise in the price of refined petrol coming out of Singapore.

She said because 90 per cent of Caltex petrol stations are individually owned, the price rise is recommended only and will not happen immediately.

Mobil spokesman Alan Bailey said the international price rise in petrol had "compressed margins".

Shell
91: 171.9 cents a litre
95: 176.9 cents a litre
Diesel: 103.9 cents a litre

Caltex
91: 171.9 cents a litre
95: 176.9 cents a litre
Diesel: 103.9 cents a litre

Mobil
91: 171.9 cents a litre
95: 176.9 cents a litre
Diesel: 103.9 cents a litre

BP
91: 171.9 cents a litre
95: 177.9 cents a litre
98: 185.6 cents a litre
Diesel: 103.9 cents a litre

Gull
91: 164.9 cents a litre
91 Regular plus (biofuel blend): 163.9 cents a litre
98: 176.9 cents a litre
Diesel: 102.9 cents a litre

- NZHERALD STAFF