Anything over 100k is not protected and normally is lost when a bank crashes. As the EU is financing the under 100k protection (because Cyprus is incapable of fulfilling its duties) it can hardly be called theft or confiscation of private savings. Its an investment loss. Iceland seized 100% of foreign bank accounts and the EU agreed that it was legal in the circumstances.
Why would anyone have over 100k in a bank account, let alone in a know basket case such as Cyprus? The Greeks moved their money abroad years ago.
If you are arriving in the UK from a country outside the European Union (EU), or you're leaving the UK to travel directly to a country outside the EU, you must declare any cash of 10,000 euros or more (or its equivalent in other currencies) to customs officers.
Have more than 5K and customs will interrogate you. Legally any police or customs officer can confiscate anything over 1K anywhere in the UK if they believe its the proceeds of crime.