The Luxembourg-based Court of Justice of the EC started on 28 April 2009 its hearing in case C-58/08, Vodafone and others.
Plans to cut the cost of roaming charges for mobile phone users in Europe could be in jeopardy if the court rules in favour of telecoms companies.
Four of Europe's largest mobile network operators - Vodafone, Telefonica O2, T-Mobile and Orange - have challenged the validity of the 2007 Roaming Regulation, which limits the rates that can be charged for using a mobile phone abroad.
New roaming charges, which were approved by the European Parliament, are due to come into force on 1 July 2009 and would cut current rates by more than 60 per cent. Under the proposals, the price charged for sending a text message while abroad would be capped at 11 cent plus VAT, compared to a current EU average of 28 cent.
The telecoms companies' case was initially brought before the British courts, challenging rules applying the legislation. The High Court in London has asked the Court of Justice of the EC to decide whether the Regulation was adopted on the correct legal basis.
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