Egypt has begun enforcing a ban on international calls made through mobile internet connections, the head of the telcoms regulator told Reuters on Tuesday, potentially boosting voice revenues at landline monopoly Telecom Egypt.

The ban will apply to the three mobile operators in Egypt -- Mobinil, Etisalat Egypt and Vodafone Egypt -- who offer internet access for computers via USB and other mobile modems, as well as via mobile phone.

The ban is on Skype on mobile internet, not on fixed, and this is due to the fact it is against the law since it bypasses the legal gateway, said Amr Badawy, the executive president of the National Telecommunication Regulatory Authority (NTRA).

Under Egyptian law, international calls must pass through a network controlled by majority state-owned Telecom Egypt, which this week reported disappointing earnings.

While only mentioning Skype by name, Badawy did not rule out extending the ban to other services in the future.

We are targeting any illegal voice traffic on the mobile (internet), Badawy said, adding that the ban was communicated to the three mobile operators earlier this week. Any traffic outside the international gateway is against the law.

Several other providers, including Google, Yahoo and Windows Live, offer Voice over Internet Protocol (VoIP) services.

The NTRA had tolerated mobile internet telephony until a drop in international call volumes over recent months pushed them to tell Egypt's operators to enforce the ban, Badawy said.

We monitor what is happening on international voice calling and it has had an adverse effect on it, he said by phone.

Internet telephony firm Skype's free calls on computers have become an internet phenomenon since the company was founded in 2002 and it has some 520 million registered users worldwide.

Skype signed a deal last month with Verizon Wireless, the first U.S. mobile operator to actively push the service, which will work on phones such as Research In Motion's BlackBerry.

Telecom Egypt offers fixed-line internet, as does LINKdotNET, owned by Orascom Telecom.

Officials from Etisalat Egypt and Mobinil were not immediately available to comment, but a spokesman at Vodafone Egypt confirmed the ban was in place.

We've been informed of the decision and we are already abiding by it, Vodafone Egypt spokesman Khaled Hegazy said.

The moves comes after the United Arab Emirates said on Monday it would not yet give VoIP licenses to international companies like Skype.

In September, India's security agencies recommended a ban on international internet telephony until a system to trace the calls was put in place.

The NTRA's Badawy said he could not say whether Egypt's ban would be extended to international voice calls made over fixed-line internet.

(Editing by Simon Jessop)

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