PUMP prices for LPG are expected to hit an all-time high in the coming days, with prices already skyrocketing to more than $1 per litre at some Victorian service stations.

The RACV is encouraging motorists whose cars use LPG to fill up now.

RACV vehicle engineering manager Michael Case said the new regional benchmark commodity price for LPG rose 33 per cent to a record high on December 1.

This was due to increased global demand for the gas as the northern hemisphere prepares for winter.

QUESTIONS RAISED OVER PREMIUM PRICES

Mr Case said Melbourne retailers were already starting to inflate their LPG prices, with 20 per cent charging 89.9c per litre this morning and a further six per cent charging 92.9c.

LPG prices also jumped to more than $1.02 per litre in some Victorian towns.

'FUEL DEAL A WIN FOR CONSUMERS'

"This is far above the rest of the market, which is selling LPG at 72.9c per litre," Mr Case said.

Mr Case said despite the global demand, service stations could not use the excuse of increased LPG production costs to justify a 33 per cent price increase as majority of Australia's LPG was sourced locally.

He was also concerned the price rise could damage LPG's reputation as a cheaper alternative fuel.

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