Saudi Arabia plans to block Whatsapp very soon if the app developers/owners didn't comply with their local regulations. I have no doubt that they might go ahead and block it, as they have already blocked the very popular app "Viber" last week.
The reason why Viber was blocked last week is because of it's "noncompliance," while Whatsapp and Skype are next on the list. And from what I have read so far, Whatsapp will be blocked more likely before Ramadan!
To read the full interview with Abdullah Al-Darrab, read the Arab News article from here.