A judge saved a sexual attacker from jail yesterday after making the man promise to write a letter of apology to the victim.

Millionaire's son Prashant Modi (33) faced up to 18 months in jail for sexually assaulting a Swedish student, but was given a six-month suspended sentence.

Old Bailey Judge Jeremy Roberts said there were exceptional circumstances, such as Modi being a "geeky" Indian not used to Western ways.

He had found himself alone with three young women asleep in his hotel room and had fallen into temptation, said the judge.

The court was told that all had been drinking champagne and vodka at a West End nightclub.

The women, all in their early 20s, had fallen asleep in his room, two on his bed and one on the sofa.

One woke to find half-naked Modi on her friend who was still fast asleep.

Modi, whose home is in New Delhi and who had never been in trouble before, pleaded guilty to sexual assault.

Judge Roberts told Modi he would suspend the sentence for two years and ordered him to sign the sex offenders register.

He told him: "Within three days you will write a letter of apology and the Crown Prosecution Service will find out if she (the victim) wishes to receive it."

It is believed to be the first time that such an order has been made in a sexual offence case.

Under new legislation, judges can make an "activity requirement" when suspending sentences. Modi was also ordered to pay £28,543 towards the prosecution costs.