TABLOIDS in the country are going to town over revelations by a South Korean actress about her affair with an opera singer.

Meanwhile the marriage of Ok So-ri and her husband of 11 years, actor Park Chul - both teen idols of the '90s - threatens to crumble, reported AP.

The furore has rekindled debate in the country about whether the 54-year-old adultery law is an old-fashioned relic, as So-ri faces possible criminal charges for her extramarital relationship.

South Korean anti-adultery laws state that those convicted face prison sentences of up to two years.

In a tearful news conference on Sunday, the 39-year-old admitted that she was involved with the opera singer for a few months last year, but stressed it was because of her loveless marriage to Park.

The admission caught many South Koreans by surprise because the couple had always been touted in the media as the ideal match.

'He and I have been living under the same roof but without any warmhearted conversation, so I suffered depression for a long time after giving birth,' So-ri said, referring to the couple's now 8-year-old daughter.

'We only had 10 conjugal relations during our 11 years of marriage.'

She quashed speculation of another lover - an Italian chef at a luxury hotel - saying that he was just a friend who taught her English and cooking.

Park Chul, also 39, immediately told local reporters that he felt 'very sad and angry' to watch his wife's mudslinging appearance before the press.

'Her words '10 times' caught my eye,' he said. 'I'm a man who has no medical problem.' Park Chul said he was filing a legal complaint for adultery charges against his wife and her two male companions, saying he has evidence of their relations.

The sensational breakup could lead to a fierce legal battle, as the adultery law can be invoked only when there is 'decisive evidence' of infidelity.

The law says that physical proof, such as photos of sexual intercourse, constitutes evidence. Photos of other acts are not sufficient documentation.

Park Chul said he has the necessary evidence, but he didn't elaborate.

The number of adultery cases filed declined to 8,720 in 2005 from 12,762 in 2000, according to prosecutors' records.

But more than 80 per cent of cases filed were either withdrawn or dropped because of lack of evidence, said prosecutors.

Supporters of the law don't want it abolished because, they say, it helps protect women's rights and prevents family breakups and declining sexual morality.

Opponents argue that the law violates privacy. South Korea's Constitutional Court has so far resisted three attempts to get the law abolished. But it faces further scrutiny.

Justice Do Jin-ki of the Seoul Northern District Court, one of two judges filing petitions because they think it is unconstitutional, said: 'The law should not come inside our bed.'

Opinion polls show that up to 70per cent of South Koreans support the law.

However, adultery is believed to be common in South Korea, where 'love motels' offer short stays and amenities - such as covers for licence plates.