Chinese director Zhang Yimou poses during a photocall to promote the film "The Flowers of War" at the 62nd Berlinale International Film Festival in Berlin in this February 13, 2012 file photo. [Photo/Agencies]

BEIJING - Film director Zhang Yimou has admitted that he and his wife Chen Ting broke China's family planning rules.

Zhang, who admits to having three children, apologized to the public via an open letter from his studio.

The letter, posted online on Sunday night, said that "the couple has two sons and a daughter and is willing to accept investigation and punishment in accordance with China's laws and regulations."

The letter denied that Zhang has a mistresses and as many as seven children to various mothers. Zhang will seek legal redress against those who have disseminated allegedly libellous stories.

Zhang, one of the fifth generation of Chinese filmmakers, made his directorial debut in 1987 with Red Sorghum and has won numerous awards  worldwide. He was chief director of the opening and closing ceremonies of the Beijing Olympic Games.

People in China who have more children than the family planning policy stipulates are usually fined. The amount of the fine is generally decided by local authorities. Jiangsu, the province in question, fines couples who have two 'extra' children five to eight times the yearly annual income of both spouses combined. Some media calculations put the sum at as much as 160 million yuan (over 26 million U.S. dollars).

China's family planning policy was introduced in the late 1970s stop the surging population by limiting most urban couples to one child and most rural couples to two, if the first child was a girl. The policy was recently relaxed: Now, if both parents are only children they are allowed a second child. In November this year, the decision to further loosen the policy was taken, allowing couples to have two children even if just one of them is an only child.

In May, media stories claimed that Zhang had remarried and had a total of seven children, one with his ex-wife, three with Chen and another three from two mistresses. The exposure had little impact at the time and there was no investigation by the local family planning bureau, until on November 29, the bureau in Wuxi City said that an agent for Zhang and Chen had arrived in the city to answer the accusations.

Zhang's story has ignited a firestorm of online public ire for celebrities who have more children than the policy allows.

"Siqingyundong" said at weibo.com that "common people are forced to have abortions, while celebrities are treated differently before the law."

Yuan Yiwen, a legal professional, wrote in Monday's Beijing News that "every citizen is equal before the law and should not be treated differently because of their social status or wealth."

Yuan queried local authorities who ignore celebrity violations until there is a media frenzy and  fierce public discussion.

"If celebrities do not abide by the law, they are abusing privileges," said Yuan. "I hope local family planning authorities implement the law equitably."