Last checked at 
MADRID, May 29 (Reuters) - Spain's anti-trust watchdog isinvestigating whether oil firms including Repsol, BP and Cepsa colluded to raise fuel prices, adding tohigh-profile investigations into oil pricing across Europe.
Competition regulator CNC said on Wednesday it had beenkeeping watch on the oil sector since finding a significant risein fuel prices, with general levels of pre-tax fuel priceshigher than those registered in neighbouring countries.
The move follows a report from energy regulator CNE earlierthis month that showed oil majors Repsol, BP andCepsa hiked fuel prices to protect profits during a period ofweak demand due to a prolonged recession.
The Spanish issues are independent of a European Commissioninvestigation which has seen the offices of oil majors BP, Shelland Statoil as well as pricing agency Platt's searched onsuspicions that oil, refined products and ethanol prices couldhave been manipulated.
The Spanish Association of Oil Product Operators (AOP) hassaid profit margins have not risen so far this year, it justlooks like they have because of changes to how costs are booked.
CNC's initial investigation will determine whether or not itlooks further into possible anti-competitive practices and doesnot imply wrong-doing, the watchdog said.
If found guilty, it said the companies could be fined up to10 percent of total sales in Spain in the preceding financialyear.
Repsol and Cepsa declined to comment. BP representatives inSpain were not immediately available to comment.
Spain has been struggling to strike a balance between highertaxes, aimed at meeting European Union demands to cut its largepublic deficit, and keeping inflation under control.
If oil companies were to reduce fuel prices, Madrid couldhave more room to increase taxes without hurting cash-strappedconsumers battling high unemployment and dire economic growthprospects.
On Wednesday, the EU extended Spain's deadline to meet itsbudget deficit goal but said the country should review its taxsystem by March, 2014, including exploring additional measuresin environmental taxation, particularly in fuel taxes.
