Melissa Miller was earning �85,000 a year when she married

Alan Miller, who has a wealth of about �17.5m, divorced wife Melissa in 2003 after running off with another woman.

In April, he was ordered to pay a �2.7m lump sum and pay off the mortgage on a �2.3m home in Chelsea, west London.

Judges dismissed his appeal saying the ruling was not excessive when assessed against Mr Miller's overall wealth.

The court heard other factors taken into account were that the marriage broke down because Mr Miller, 41, went off with another woman and by marrying Melissa, 35, he had given her an expectation of a significantly better standard of living.

In under three years she has achieved a modest fortune Lewis Marks QC, representing Mr Miller

Melissa, an American, met Mr Miller shortly after arriving in Britain in 1995 to start work at a pharmaceutical company in Cambridge on a salary of �85,000 a year, the court heard.

On Friday, Lord Justice Thorpe said their marriage had been portrayed as a �5m pay-off for a mere two-and-three-quarter years of marriage.

"In my judgment the reality is very different," he said.

"The responsibility for the collapse of that endeavour must in part be ascribed to the husband's decision to end the marriage."

'Brain damage cheaper'

He said if he had been involved in the decision over the amount of the settlement he did not think he would have gone so high.

But he said the award fixed by Mr Justice Singer, who made the original ruling, was not excessive although it was at the top end of the permissible bracket.

Earlier, Lewis Marks QC, representing Mr Miller, told judges his client would have been better off if he had knocked down his wife in his car.

"In under three years she has achieved a modest fortune.

"If my client had knocked her down with his motor car, and she had suffered severe injuries - brain damage and losing the ability to have children - at most the damages would be �2m," he said.