I think the real question is when you implemented that restriction in your Terms of Service? Also, why isn't Russia mentioned alongside the other restricted countries, given that it's a requirement of your licensee? It appears that you introduced the rule after the fact, and I don't think you have the right to confiscate the player's funds without notifying them in advance.
When exactly were the terms put into effect, and did you send out an email notification about the changes to your Terms of Use?