Honeymooners Liza Minnelli and David Gest had thrown themselves into the London party scene with relish, dining with the capital's A-list celebrities and dancing until dawn at the most fashionable clubs.

But while they were being chauffeured back to their hotel after a television interview, they were confronted by an altogether more seamy slice of London life.

As their Mercedes stopped at lights at the end of a week when street crime was once more on the top of the political agenda, a robber tried to grab Ms Minnelli's £10,000 necklace. It was only the alertness of the driver which prevented the entertainer becoming just another crime statistic.

The newlyweds were being driven back to the Lanesborough hotel on Thursday after Ms Minnelli's interview with Jonathan Ross at the BBC studios in White City. Their car had stopped at a red light near Holland Park tube station at about 9.15pm. The night was mild and one of the blacked-out windows of the car was half down.

A man thrust his hand through the window towards Ms Minnelli. She thought he was an autograph hunter. The chauffeur knew better.

As the attacker made a grab for the singer's diamond encrusted crucifix, the chauffeur closed the electric window. The attacker, who had two accomplices, tried to force the door open but the driver put his foot down and drove off.

The couple, who were also being followed by a photographer, stopped off for a coffee in Notting Hill a few minutes' later, where they described what had happened, before being driven on to their hotel on Hyde Park Corner.

The couple married in New York last weekend. It had been expected that they would spend their honeymoon in Thailand. However, they arrived at Heathrow on Concorde on Wednesday evening. Gest said: "We're just going to have some fun."

They are due to return to the US today but the incident has not ruined their stay in London. They issued a statement, saying: "We're New Yorkers so nothing scares us."