Movie director Zhang Yimou has disputed an official calculation of his earnings used to determine a fine he is due to pay for violating the family planning policy, officials in Wuxi, Jiangsu province, said on Monday.

Zhang and his wife, Chen Ting, submitted a document on Friday to the Binhu district health and family planning commission, querying the official estimate of his income over the past few years, according to a post in the commission's official micro blog.

The commission notified the couple of the amount of the fine at the end of December, according to the blog post.

However, the amount has not been made public because the case is still being processed, an official from the bureau told China Central Television.

The commisson said it will reply to Zhang in time and levy the fine according to the law.

Zhang and Chen admitted to having two sons and one daughter between 2001 and 2006, before they were married in 2011.

China's family planning policy, introduced in the late 1970s to rein in the country's booming population, limits most urban couples to one child and most rural couples to two if the first child is a girl. The policy was recently relaxed, allowing couples to have two children if one of them is an only child.

Those who violate the policy face hefty fines — normally several times the couple's combined annual income.

A lawyer for the Binhu district health and family planning commission told Xinhua News Agency that Zhang's earnings in 2000, 2003 and 2005 totaled 3.6 million yuan ($595,000).

After calculations based on the combined household income, Zhang could be fined about 7.3 million yuan, said Li Wei, an executive partner at the Fada law office in Beijing.

"For me and my parents, we prefer to have more children, according to the traditional view that they can bring greater happiness," Zhang told Xinhua.

"My father told me before his death that he hoped I could have a son to continue the family line, and my mother also believed that with more children, they could have more companions."

Previous media reports have claimed that Zhang is the father of seven children: one with his ex-wife; three with his current wife; and another three with two mistresses.

In an open letter on Dec 1, Zhang admitted he and his wife have two sons and a daughter and are willing to accept an investigation into the matter and any resulting punishment. He also apologized to the public.

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