This item is updated with additional statistics from the Dept of Health London April 14th. 2010
Is the UK and the British Citizen being ripped off by France? The charge to the UK for pensioners in France is 192% higher than for pensioners in Italy and healthcare in Italy is totally free. This link also links in turn to all the relevant legal extracts. It also indicates the way forward.
In the meanwhile if you live in France you must follow the French law and pay up!