As they sipped bottles of wine under the dim glow of ornate black wrought iron chandeliers, celebrities as influential as Sir Elton John, as popular as Will Smith and as fashionable as Gwen Stefani toasted Victoria Beckham’s 34th birthday.

The newest additions to Victoria’s Los Angeles network – actresses Kate Beckinsale and Eva Longoria – were also there, as was supermodel Heidi Klum and her rock star husband, Seal.

Of course, her profile has been boosted in no small measure by her friendship with Tom Cruise’s wife Katie Holmes, who also made an appearance at Via Veneto.

The two women were inseparable during the first few months of Victoria’s new life after being introduced to each other by their husbands – who have been friends since Tom went to watch David Beckham play in a Real Madrid match in 2004.

While Victoria gave Katie advice on fashion and motherhood, Katie – five years Victoria’s junior at 29, similarly photogenic and already a Hollywood A-lister – guaranteed the paparazzi’s interest by happily posing for limitless picture opportunities when the pair were together.

Their’s has, even by the mercenary standards of Hollywood acquaintances, been a relationship of spectacular mutual benefit.

But it is also one that, The Mail revealed, could be on the brink of falling apart.

The Beckhams and the Cruises vehemently deny a rift and maintain they are as friendly as ever but sources close to them insist Katie and Tom’s appearance at Via Veneto was little more than a PR stunt and that there is a distinct, and ever widening, chasm between the two women.

It is caused, they say, by Victoria’s reluctance to embrace Scientology, Tom’s religion, and her apparent influence over Katie’s weight – weight, of course, being Victoria’s religion.

It is perhaps inevitable that the two couples would eventually fall out.

Even disregarding the age gap, Victoria is the more forceful woman, known for her strong beliefs and said to be in the driving seat of her own marriage in much the same way Tom appears to be in control of his.

So when it comes to issues as delicate as religion and body image, Victoria is no less likely to surrender her opinion than Tom would do his.

One well-placed source says, “Katie and Tom want to surround themselves with fellow Scientologists these days, and they are distancing themselves from anyone who is not a believer. For Tom, a non-believer like Victoria is very dangerous. She is opinionated, strong-minded, privately against Scientology and has voiced her doubts.”

Her refusal to subscribe to the religion – that has at its core the study of the spirit and the belief in an immortal soul that passes from one body to the next through countless reincarnations spanning trillions of years – will surely have disappointed Tom.

His closest Hollywood friends are those who either embrace it or are open to its ideology, such as Jennifer Lopez and her husband Marc Anthony, and Will Smith and his wife Jada Pinkett.