Mark Thatcher denied residency in Monaco

Sir Mark Thatcher will not be making a new life for himself in Monaco because its ruler, Prince Albert, wants to improve the principality's unsavoury financial reputation.

Baroness Thatcher's only son had hoped to gain permanent residence in the mini-state, but yesterday he had his application for a renewal of his temporary residency refused.

Prince Albert, the only son of the late Prince Rainier and Princess Grace, marked his intention to erase the shady image of the country as a centre for tax evasion in his inaugural speech last July.

"Ethics cannot be chopped and changed," he said then. "Money and virtue must go together permanently. The importance of the financial situation of Monaco requires an extreme vigilance to avoid the development of financial activities which are not welcome in our state."

A source close to Monaco's ruler was quoted in Le Figaro as saying: "This time, it's an outside personality who will pay for the new situation. But a few residents installed here for a long time might well have their share of bad surprises."

The 2sq km principality has 30,000 residents but almost 130,000 bank customers with combined savings estimated to be £42bn, a grand prix street-circuit and a plethora of casinos.

Sir Mark is believed to have savings of £60m, much of which is reported to be invested in off-shore accounts. In April, Sir Mark was refused a visa for the United States. He was intending to visit his two children, Michael, 15, and Amanda, 11.

He is not welcome in South Africa either. In January he was convicted of helping to finance a failed coup in Equatorial Guinea in a South African court. He was fined £250,000 and given a four-year suspended prison sentence. Lady Thatcher, 80, paid for her son's £265,000 bail while he was kept in custody by the South African authorities investigating the allegations.

When visiting London, Sir Mark lives with his mother at her home in Belgravia, central London.