EU ministers urged the European Commission and regulators to check on telecom operators who prioritize bandwidth for certain services, giving leverage to complaints about mobile firms around the world blocking Web-call services such as Skype.

Ministers urged the pan-European regulator and the European Commission to monitor mobile companies' traffic management to ensure that they do not hamper net neutrality, meaning that all services are treated equally.

The regulator, BEREC, says infringements of net neutrality, in which some Internet traffic like voice calls is blocked in favor of other data, are infrequent, but ministers are concerned that some services are being throttled.

BEREC will publish a joint report from regulators in the 27 EU member states in February on whether telecom firms respect the principle of net neutrality.

Microsoft's Skype service says it is either blocked or overpriced by mobile operators, who see its low-cost service as a threat to their business. Skype's customer base is forecast to reach 150 million by 2016, according to Juniper Research.

A report by the voice over Internet Protocol (VoIP)association, VON Europe, says Vodafone Group Plc restricts access to Web-based calls on pay-as-you-go deals, while some mobile providers do not allow VoIP at all, including France Telecom's Orange, Bouygues, Germany's E-Plus and its parent group, Dutch provider KPN.

The Netherlands passed a law on October 3 banning mobile firms from charging customers extra for Web-based call services.

(Reporting By Claire Davenport; Editing by Rex Merrifield and Helen Massy-Beresford)