BILLIONAIRE the Aga Khan has paid out 54 million to divorce his second wife. Six years ago, his split from his German-born former pop singer wife, the Begum Inaara Aga Khan, was billed as potentially the most expensive divorce in history with a 500 million price tag. But on Friday, papers filed at the Appeal Court in Amiens in northern France revealed a deal with his second wife, Begum Inaara, has finally been struck - at a tenth of that figure. The Aga Khan - who is worth 6 billion, owns 600 racehorses and has homes on five continents - moved legal proceedings across the Channel in the hope of getting a better settlement than he would have expected in the UK. And Saturday night he appeared to have saved himself a fortune by shifting the case to France. The payout is by far the largest ever awarded in France, where civil settlements are comparatively low. The deal between the Aga Khan, 73, and the former Gabriele zu Leiningen is understood to include the Berkshire estate where she lives with their 11-year-old son, Prince Aly. The settlement follows claims by Begum Inaara, 51, that her husband was seeing an air hostess. Papers filed in the French court reveal that relationship between the Aga Khan and his wife had 'irretrievably broken down within a couple of years of their society wedding on the Aga Khans estate at Aiglemont, north of Paris, in 1998. DM