'There is going to be a big increase in divorce cases as a direct result of this judgment, where assets built up before, during and after a marriage are going to be attacked by the economically weaker spouse.'

He warned that people should be very clear going into a marriage about what would be considered a marital asset. Prenuptial agreements, while not binding in Hong Kong, might help to indicate the intentions of the parties going into the union, he said.

Agreements drawn up before the March judgment would probably now be redundant.

Mr Dearle also warned strongly against trying to hide assets from a spouse, as discovery could lead to serious consequences, both financial and legal.

In the judgment, Mr Justice Peter Cheung Chak-yau, Madam Justice Maria Yuen Ka-ning and Mr Justice Johnson Lam Man-hon brought Hong Kong's divorce law into line with that of England and Wales.

Until the judgment, Hong Kong's courts had assessed what the 'reasonable requirements' of the spouses were and divided the assets accordingly; leftover assets were then awarded to the breadwinner, usually the husband.

However, the court said this approach was outdated given that society's view of marriage had changed.

'On marriage, the parties commit to sharing their lives,' Mr Justice Cheung, writing the lead opinion, said. 'It is a partnership of equals.

'On divorce, the principle and spirit underlining the union should be reflected in the division of the family assets,' Mr Justice Cheung said.

'[It] should proceed on the basis of fairness and this necessarily means there is no room for discrimination between husband and wife.

'The starting point is equality in division unless there is a good reason to depart from it.'

However, Jacques Sherman of Sovereign Trust, a trust and offshore services company, said it was up to the court to determine what was fair in the circumstances. 'The difficulty with the court's approach is that the concept of fairness is itself rather open to interpretation,' he said.

'In circumstances where one party has taken precautions to guard his or her wealth from potential spousal claims, and the spouse of that party recognises and accepts those arrangements, it might well be argued that for the court to strip away that protection by way of an order is in itself an unfair act.'

He said the case brought into focus the fact that marriage and the arrangement of financial affairs required careful planning. 'To ignore one's financial affairs, either in a situation of wedlock or otherwise, is to invite uncertainty and difficulty.'