Fuel prices have risen at most service stations on the eve of the school holidays, as oil companies recover higher import costs.

The AA has accepted the need for firms to raise petrol and diesel by up to 4c a litre but industry minnow Gull is holding its ground until at least tomorrow. "We can't see any reason to lift prices now," general manager Dave Bodger said yesterday.

"It's true that international oil prices have increased but they are volatile and partially offset by the strong Kiwi dollar.

"The AA called for prices to ease the other week, and we see any move to increase Gull fuel prices before Friday as unnecessary."

Most main centre stations carrying the major fuel brands have lifted the price of 91-octane petrol to $2.10 a litre, and diesel was selling last night at BP, Mobil and Z Energy [formerly Shell] outlets for $1.50 after rises of 3c or 4c.

Caltex stations increased diesel by just 2c, to $1.47.

But they are all being undercut for now by Gull, which was still selling its 91-octane blend of biofuel and petrol for $2.04 at traditional sites and $2 at its seven unstaffed North Island stations, including two in Hamilton and one at Ti Rakau Drive in Auckland.

That has left the Australian-owned company crowing about offering petrol for up to 10c less than its multinational competitors.

Its diesel remained last night at $1.46 a litre at traditional sites and $1.42 at unstaffed stations.

AA spokesman Mark Stockdale, who criticised major companies last week for not selling cheaper fuel after a big drop in world oil prices last month, said yesterday the latest increases were "not unexpected".

"Unfortunately oil prices have been rising by about US$10 a barrel since the last changes at the pumps about a fortnight ago."