The most populous country in the world faces the threat of a new surge in its population as Chinese nouveaux riches ignore penalties for violating the strict “one couple, one child” family planning policy.

Zhang Weiqing, director of the National Population and Family Planning Commission, said that a population explosion was an unwelcome possibility. China has an officially estimated total of 1.3 billion – or 20 per cent of the world total.

However, rising incomes and an increase in marriages among underage young people in rural areas are putting goals to limit population growth under pressure. Mr Zhang said: “The number of rich people and celebrities having more than one child is on a rapid increase, and nearly 10 per cent of them have three.”

Since the late 1970s, China has limited most urban couples to one child – although rural families are often allowed to have two – in an attempt to control the rise in population and to conserve natural resources. Officials say that the strict policy has prevented as many as 300 million births.

The Chinese population exploded during the rule of Chairman Mao, who urged people to have many children – part of his “human wave” defence policy, when he feared attack by the United States or the Soviet Union during the 1950s.

Many rich and self-employed people are happy to pay the stiff fines imposed by the Government for having a second child. They have no need to fear rules that require government organisations to dismiss one member of a couple if they ignore the one-child policy. And with the introduction of private schools, they are not deterred by rules that prevent second children from obtaining a place at a state school.

Fines vary widely, with farmers often facing penalties of about 5,000 yuan (£350), or more than their annual income. However, in cities the fines can be as much as 50,000 yuan – still too low to deter the rapidly expanding numbers of newly rich. And if a family refuses to pay the fine there is little that officials can do.

One young Chinese said: “What can they do? They can’t kill the child because it’s already there.” To try to deter people from contributing to a population surge, the Government has said that it may record the names of the rich and famous who ignore the rules on an official “bad credit” file. They may be disqualified from honours and even named and shamed in public. One multimillionaire businessman in Beijing with three children aged between 5 and 14 scoffed at the rules. “I have plenty of money and if I want to spend that money on having more children I can afford to.”

Many Chinese are willing to pay whatever is required if it means that they can have a son. Traditionally, only sons can carry on the family line and enact the rituals of honouring ancestors.

The countryside is scattered with slogans painted on village walls, encouraging families to give as much emphasis to having a daughter as to giving birth to a son. However, such exhortations tend to fall on deaf ears. Farmers want sons to work the land as well as to bring honour on the family. And as farmers become more prosperous, they are marrying younger. The Chinese Constitution says that men may marry at 22 and women at 20, with late marriages and later childbearing encouraged to keep population growth down.

Mr Zhang said: “Early marriages are still prevailing in some parts of the country, which goes against the family-planning policy.”

The Chinese Government has pledged to keep the population under 1.36 billion in 2010, and below 1.45 billion in 2020. But already the one-child limits apply to only 35.9 per cent of the population and those goals are increasingly in jeopardy.

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