A former City banker turned biotechnology researcher faces financial ruin if his former wife wins her battle to bind him to a prenuptial contract, the Supreme Court was told yesterday.

Nicolas Granatino is challenging his £1 million divorce settlement with Katrin Radmacher, a German heiress said to be worth £100 million.

The case before nine Supreme Court justices will determine if divorcing couples in England and Wales should be bound by pre-marriage agreements on how their assets will be split.

The couple agreed before marriage not to claim a penny of each other’s fortune if the marriage failed, but Mr Granatino, 38, a French citizen, says that when he signed he did not know the full extent of his wife’s wealth and that he would suffer personal hardship if the agreement were upheld.

Mr Granatino was a banker with J P Morgan on £300,000 a year when the couple met. In 2003 he left his job to pursue a doctorate at the University of Oxford and is now a researcher on £30,000 a year. His former wife is heiress to a paper company and said to be one of the richest women in Europe.

The couple, who divorced in 2007, have children aged 10 and 7 and spent most of their married life in Chelsea, West London.

Mr Granatino has taken his case to the highest court in the land after the Court of Appeal cut his original divorce settlement awarded in the High Court from more than £5 million to £1 million, saying “decisive weight” should be given to the prenuptial contract.

Source: Times Online