Some petrol companies have raised prices, but companies say they have tried to spare the residents of Christchurch.
BP, Mobil and Caltex raised prices for 91-octane petrol as high as $2.08 on Tuesday. Shell is raising prices later in the evening.
Diesel is also going up by about five cents a litre.
All the petrol companies say unrest in the Middle East and a dip in the New Zealand dollar due to the earthquake have pushed up oil prices.
But BP, Shell and Mobil say they will not raise prices in Christchurch, while Caltex says it is not raising prices anywhere in the South Island.
The Automobile Association has commended the big oil companies for sparing Christchurch.
Spokesperson Mark Stockdale says that under normal circumstances the pump prices would have gone up last week. He says the companies may not need to push prices higher in the short-term.