PETALING JAYA - Unreasonable behaviour as grounds for divorce could be any action that one finds to be intolerable to continue living with the spouse anymore, said family law practitioner Foo Yet Ngo.

She said this behaviour could have taken place over a short or long period of time or for cumulative or isolated episodes.

"However, it is very subjective because what may be unacceptable to one side may be fine with the other," she said when contacted.

Such behaviour, she said could be minor annoyances or serious problems like mental or physical abuse.

News reports have emerged that former Miss Malaysia Pauline Chai had filed for divorce from tycoon Tan Sri Khoo Kay Peng in London last month after 43 years of marriage.

According to the reports, she had cited "unreasonable behaviour" as the grounds for divorce and that the courts could award her up to £500 million (S$964 million), which might be the largest divorce settlement in British history.

Foo said that in such cases, the court would make its decision bearing in mind the subjective attributes of the individuals involved as well as what would be unreasonable between the two parties.

Malaysian courts also divided assets in a divorce case based on the respective contribution of the two parties towards the acquisition of assets, she said.

"This involves direct contribution such as being in charge of financial payments and company finances. Indirect contribution is through looking after the family, children and household finances," she said.

"Besides asset division, Malaysian law provides for a monthly maintenance (or alimony) payment, while in the United Kingdom it could be given in a lump sum," she said, adding that a lump sum payment could be given provided both parties were in agreement.

She said British courts tried to work towards a clean break policy in ordering division of assets, including the lump sum alimony payment.