An official from the state sponsored All China Women's Federation said the threat was prompted by the rising number of cases of married men supporting mistresses in the city.

China's parliament is currently considering revisions to the country's marriage law, which would introduce similarly harsh penalties for extra marital affairs.

But some Chinese newspapers have voiced opposition to the proposals, with citizens complaining that they would amount to state interference in their private lives.

Hard labour awaits cheating husbands

Divorce rates in China are rocketing and the resulting break-up of families has become an issue of growing public concern.

The Guangzhou authorities are threatening such extreme measures in an effort to reverse the trend.

The warning - which was made in a circular - said married men who provided financial support for their mistresses would be treated as bigamists. It said officials would have the right to intervene in cases deemed harmful to society even if no formal complaint was lodged.

Re-education

Those who ignore the warnings could be sent for what China calls re-education through labour, in other words a period of up to three years in a labour camp without trial.

Some Hong Kong men have mistresses across the border

Among those involved in such affairs are men from nearby Hong Kong who can easily maintain mistresses on the Chinese mainland without the authorities being aware that they have a wife across the border.

Huangguolin, a village just across the border from Hong Kong is often referred to as "concubine's village" because of the large number of mistresses of Hong Kong men living there.

In October one Hong Kong woman threw her two sons to their deaths from a building and then jumped herself after finding out about her husband's mainland mistresses.

The husband has been at the centre of intense media attention because the day after the deaths he returned to his mistresses in the Chinese border city of Shenzhen.