(Adds Coles comment)
SYDNEY, Jan 15 (Reuters) - Australian authorities said onThursday they would start investigating petrol stations withoutwarning for possible price fixing after a lawmaker accused someof failing to pass on huge falls in the oil price to consumers.
The probe will put additional pressure on firms like ChevronCorp and its half-owned retail subsidiary CaltexAustralia Ltd, Britain's BP Plc and Dutch Vitol which dominate Australia's service station industry.
It may also impact large domestic retailers like supermarketcompanies Woolworths Ltd and Wesfarmers Ltd's Coles, which run customer loyalty programmes that rely on fueldiscounts.
Already they have watched the price of petrol that consumerspay at the pump slide by more than a third since July last yearas the spot price of oil plunged amid concerns of globaloversupply.
But the Australian government earlier this month saidservice stations in some regional areas seem to have cut pricesby less than those in cities, where there is more competition,and ordered a three-year investigation into how they decideprices.
On Thursday, the Australian Competition and ConsumerCommission said it would use its compulsory informationgathering powers to produce eight reports a year on petrolpricing, up from one currently, noting that the gap betweenregional and city prices has tripled since July.
"That is very hard to understand and we are very concernedabout that," ACCC commissioner Rod Sims told reporters.
"Whatever justification there is for the gap between cityprices and rural prices, once you get a reduction in theinternational price of petrol, that should flow on generallythroughout the country."
A Caltex spokeswoman told Reuters that the ACCC's ownanalysis had found petrol price moves in regional locations tendto lag those in larger cities because of slower productturnover, and "this phenomenon is again being seen".
A BP spokeswoman said the company had supported the ACCC'sfuel price monitoring program since it started producing annualreports in 2008, while a Coles spokesman said the company'sservice station business welcomed the investigation.
Spokespeople from Woolworths and Vitol declined to comment.
Petrol pump prices are not regulated in Australia but theACCC has used anti-cartel laws to fight price fixing by largeplayers.
In August last year, the regulator launched Federal Courtaction against petrol price information service Informed Sourcesand several retailers, alleging they were collaborating on pricemovements.
Informed Sources has maintained it is a private companywhich collects information from its own surveys and petrolretailers, based on publicly available information. (Reporting by Byron Kaye; Editing by Joseph Radford and RichardPullin)
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