Spanish sports leaders are angry over a European Union probe targeting Real Madrid, Barcelona and five other clubs for possibly having received illegal state aid.

Miguel Cardenal, head of the Superior Sports Council, says the probe is causing "grave damage" to Spanish football's reputation and questioned the motives behind the EU investigation.

Speaking at a breakfast sports meeting yesterday, he said the EU was saying "that state aid is widespread in Spanish football and this explains the great success our clubs have had, and this is absolutely false".

Real Madrid president Florentino Perez was equally annoyed and said he believed "there is a campaign against Spanish football".

Brussels is notably looking into whether Real, Barcelona, Athletic Bilbao and Osasuna benefited unduly from their status as associations owned by their members, which pay a 25-percent tax rate instead of the usual corporate rate of 30 percent.

The European authorities also want to know whether the clubs enjoyed unfair exemptions from social security contributions and tax debts.

"I think there is a campaign against Spanish football and I think it is bad," Perez said.

"The difference between the corporate tax rates of 25 percent and 30 percent has been so damaging to Real Madrid."