And it's hard to take anything seriously that was once chaired by Moammar Gadhafi.
There's a good link from your Wikipedia page that goes through the entire history of this declaration.
http://www.ohchr.org/Documents/Publicat ... ev.1en.pdfNo. It is not a law. If it is there are a lot of countries breaking it. Did you see where they abolished the death penalty. Iran signed on, as did Chairman Qadhaffi and Libya.
Check out some of the other things they agreed to in the link. If this is a law, and I could not find where that specific guideline of withdrawing citizenship was a law - is there anybody who is not breaking the general agreements in that covenant.
Even if you could convince me it is an actual law, what good would a law be that nobody, including the chair of the organization responsible for it obeys.