Pre-nuptial agreements could become legally enforceable in this country following a groundbreaking court ruling.

German heiress Katrin Radmacher has reversed a previous court decision to award her former husband, Nicolas Granatino, £5.8m of her £100m fortune, regardless of their contract.

Mr Granatino, who is French, had agreed not to claim if the couple divorced. 'Pre-nups' are binding in France and Germany where the couple signed their contract, but not in England where they were married.

The Court of Appeal ruled in favour of Miss Radmacher that pre-nup agreements should be taken into account when marital assets are divided.

It is expected that Mr Granatino will apply for permission to take his case to the House of Lords.

Commenting on the Court of Appeal ruling, Alex Mattur at Rowlands, said: "This judgment from three senior judges has wide-ranging implications for divorce cases involving wealthy individuals in England and Wales. It suggests that that pre-nuptial contracts will carry significant weight and influence the judge when the court is asked to determine how the parties' assets are shared."

The couple's pre-nuptial agreement was signed in Germany before the couple married in London in 1998. They divorced in 2006 and a High Court ruling last year awarded Mr Granatino £5.8m.

Miss Radmacher's counsel, Richard Todd QC, told the Court of Appeal that the freedom to agree a contract was "at the heart of all modern commercial and legal systems".

He added that Miss Radmacher had never said her former husband would leave the marriage with nothing. The Court of Appeal judges ruled that Mr Granatino's settlement of £5.8m should be cut to £1m in lieu of maintenance. Mr Granatino's debts, of about £700,000, are also to be paid off by the heiress, who had always agreed to this part of the settlement.