The UK’s four largest mobile operators have been given clearance to take a challenge over the EU roaming law to the European Court of Justice, reports the U.K.’s Financial Times. According to the report, O2, Orange, T-Mobile and Vodafone allege that Viviane Reding, European Commissioner for Information Society and Media, had no legal right to introduce the law, which forced the operators to cut the charges they impose on customers for calls outside their home countries. A London high court judge has agreed to refer the issue to the European Court of Justice.

Earlier this year the European Commission passed a law that forced operators within the EU to limit the price of making and receiving calls when abroad to €0.49 and €0.24 a minute, respectively. By 2009, the E.U.’s price ceilings are set to drop further, to €0.43 a minute for making calls abroad and €0.19 for receiving them. According to the European Commission, the rules have brought down the cost of using mobile phones abroad within the EU by 60 percent.