The competition watchdog is scrutinising petrol discount schemes offered by supermarket giants Coles and Woolworths.

Motorists can save up to 40 cents a litre by using a “shopper docket” to buy discounted fuel but the growth in such schemes during the past decade has driven many service stations out of business.

Australian Competition and Consumer Commission chairman Rod Sims says investigators are examining the schemes to see if competition is being undermined.

“The ACCC supports initiatives which provide benefits to consumers however it is necessary to assess such schemes to consider their long-term effect on competition and prices,” Mr Sims said in a statement today.

“The ACCC is currently assessing whether long-term consumer detriment could arise from the size of the shopper docket discounts and the frequency and duration of these offers made by Coles and Woolworths Caltex.”

Mr Sims said the investigation was complex and likely to take some time as the ACCC worked with industry participants to gather information.

Assistant Treasurer David Bradbury said action needed to be taken against uncompetitive practices.

“Whilst we are very concerned to ensure that consumers and motorists are always able to get the best value at the bowser, we want to make sure that if there are any uncompetitive practices occurring within the petrol sector, that they are rooted out,” Mr Bradbury said in Sydney today.

“If promotions or various schemes ... on the one hand appear to give benefits but on the other might belie some uncompetitive activity then of course we would expect that those matters would be dealt with.”

Motorists are generally given a 4-cent a litre discount for every $30 they spend at Coles and Woolworths but in some offers consumers are given 40 cents a litre off if they spend more than $300 on groceries.

The West Australian

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