This month the Communications and Information Technology Commission (CITC) banned Viber, another such tool, which like WhatsApp is hard for the state to monitor and deprives telecom companies of revenue from international calls and texts.
The kingdom appears to be making a greater push for more control over cyberspace as Internet and smart phone usage soars, in part due to strict laws that limit opportunities for people to mix in person.
"We have been communicating with WhatsApp and other similar communication platforms to get them to cooperate and comply with the Saudi telecom providers, however nothing has come of this communication yet," Abdullah Al-Darrab, governor of the CITC, told Arab News.
Al-Darrab said Viber was blocked last week for non-compliance, and that WhatsApp and Skype may be next on the list.
Asked when WhatsApp services would be blocked, the CITC chief said it was highly likely to be before the holy month of Ramadan which is expected to start on July 9.
The regulator issued a directive in March saying tools such as Viber, WhatsApp and Skype broke local laws, without specifying how.
Local media reported at the time that Saudi Arabia's three main operators Saudi Telecom Co, Etihad Etisalat (Mobily) and Zain Saudi had been asked to tell CITC if they were able to monitor or block such applications.
Mobile penetration was 188 percent by the end of 2012, CITC data shows. Saudi Arabia now has 15.8 million Internet subscribers and the average user watches three times as many online videos per day as counterparts in the United States, according to YouTube.
Conventional international calls and texts are a lucrative earner for telecom operators in Saudi Arabia, which hosts around nine million expatriates. These foreign workers are increasingly using Internet-based applications such as Viber to communicate with relatives in other countries, analysts say.
© Thomson Reuters 2013
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