For richer, for poorer: couples can make a deal before the big day

At 9.45am yesterday, the UK Supreme Court ended a long-running

acrimonious divorce case by ruling in favour of a German millionairess and upholding the pre-nuptial agreement signed by Katrina Radmacher and her ex-husband. The decision slashed Nicolas Granatino's divorce settlement from more than 5m to 1m and the news spread quickly.

"We had our first call from someone inquiring about setting up a pre-nup not long after the decision was announced," says Mr Salter, a partner in Leeds law firm Mills and Reeve and president of the International Academy of Matrimonial Lawyers.

"The result wasn't a huge surprise, but we were surprised that it was passed with an 8-1 majority as we had been told the bench was split. The issue of pre-nuptial agreements and whether they would ever be upheld in this country has been around for some time. This case has gone a long way to clarifying the situation and has given the green light to British couples wanting a formal safety net."

Radmacher, heiress to a paper company fortune, and her former husband, a French investment banker who became an Oxford University researcher, signed their pre-nup in 1998.

In it, Granatino agreed not to lay any claims to his wife's money in the event of their split.

However, when they divorced in 2007, after spending most of their married life in London, he was awarded 5.85m by a High Court judge.

Radmacher, thought to be worth 100m, appealed and yesterday's ruling potentially brings Britain in line with America and the rest of Europe when it comes to enforcing pre-nups.

Such deals have been commonplace in celebrity circles for years – Catherine Zeta-Jones reportedly had a "no cheating" clause inserted to her own pre-nup prior to marrying Michael Douglas, and Tom Cruise is believed to have promised his wife Katie Holmes 22m in the event of a divorce. Now many British lawyers are predicting the case will cause the current trickle of British applications to turn into a torrent

"Clearly this was a case which involved a vast fortune, but there are many couples, with more modest assets, who would benefit from a pre-nuptial agreement," says Mr Salter.

"Couples thinking of marrying, who have children from a previous relationship, may want to ring-fence some of their own cash or assets as an inheritance and there are others who have already gone through the pain and financial hurt of a divorce for whom it's a case of once bitten, twice shy.

"Increasingly, pre-nups are also driven by parental involvement as a way of preventing a family's fortune from ending up in the hands of

a third party if one of their children get married and subsequently divorce."

In this country, the simplest pre-nup agreement costs between 500 and 700, while more complex cases, often involving overseas couples and foreign assets, can run into thousands.

Such expense, at a time when couples are also booking reception venues and ordering wedding rings, can seem a decidedly unromantic way to

start married life. However, according to Mr Salter, it's just a question of perception.

"Many people think the whole idea of a pre-nuptial agreement is

terribly unromantic," he says. "For some people, deciding who gets what before vows have even been exchanged, is a sign the marriage is over before it's even begun, but that's only because it's an alien concept.

"We take out insurance against having our homes burgled and dying prematurely – a pre-nuptial agreement is really only insurance in case of divorce.

"Couples do go their separate ways and once the division of their

assets is put into the hands of the courts, the process can be incredibly stressful and the outcome unsatisfactory.

"These kind of agreements give some predictability and certainty if the worst does happen, and having everything out in the open right from the start is seen by many couples as a positive step.

"I even know some couples who have a pre-nup signing ceremony where

they pop open a bottle of champagne."