Two retired senior Chinese officials are engaged in a battle with one another to sway Beijing's new leadership over the future of the one-child policy, exposing divisions that have impeded progress in a crucial area of reform.
The policy, introduced in the late 1970s to prevent population growth spiraling out of control, has long been opposed by human rights and religious groups but is also now regarded by many experts as outdated and harmful to the economy.
Former State Councillors Song Jian and Peng Peiyun, who once ranked above cabinet ministers and remain influential, have been lobbying China's top leaders, mainly behind closed doors: Song wants them to keep the policy while Peng urges them to phase it out, people familiar with the matter said.
Their unresolved clash could suggest the leadership remains torn over one of China's most divisive social issues, said a recently retired family planning official. How quickly it is settled may shed light on whether new President Xi Jinping will ease family-planning controls on a nation of 1.3 billion people.
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"The government needs to take care of the various voices," the former family planning official said.
For decades, Peng and Song - both octogenarians - have helped shape China's family planning policy, which has seen only gradual change in the face of a rapidly ageing population that now bears little resemblance to the youthful China of the 1970s.
They have starkly different views of China's demographics.
From 1988 to 1998 Peng, 83, was in charge of implementing the one-child policy as head of the Family Planning Commission. In the mid 1990s she became Beijing's highest ranking woman, serving as state councilor, a position superior to a minister.
Like many scholars, she now believes it is time to relax the one-child policy. She first revealed publicly that her views had shifted at an academic conference in Beijing less than a year ago, a change rooted partly in economic concerns.
Many analysts say the one-child policy has shrunk China's pool of labor, hurting economic growth. For the first time in decades the working age population fell in 2012.
By contrast, Song, 81, whose population projections formed the basis of the one-child policy, argues that China has limited resources and still needs a low birth rate to continue economic development. Otherwise, he has written, China's population would skyrocket, triggering food and other resource shortages.
It is not unusual in China for retired senior officials to influence highly sensitive political issues. Last year former President Jiang Zemin, now 86, played a key role in selecting the new members of the politburo's standing committee.
A source close to Peng quoted her as saying that she recently wrote a letter to top officials in the new government, including Premier Li Keqiang, expressing her views. She sent the letter around the same time that Song had sent one of his own to the senior leadership, just before the 18th Communist Party Congress last November, the source added.
Reuters has not seen copies of the letters, but has been told of their contents by the recently retired official from the Family Planning Commission.
Peng declined to be interviewed for this article. Song also declined, but mailed a previously published essay to Reuters that gave his stance on China's population situation.
Historic Rethink Underway
There are signs that China may loosen the one-child policy.
Former leaders Hu Jintao and Wen Jiabao both dropped the phrase "maintain a low birth rate" in their work reports to the party Congress in November - the first time in a decade that major speeches by top leaders had omitted such a reference.
Last month, Beijing merged the Family Planning Commission with the health ministry and shifted population policymaking to its powerful economic planning agency, the National Development and Reform Commission - for the first time putting demographics at the heart of economic policy-making.
If the government scraps the one-child policy, it would affect the lives of millions of Chinese and affect policy-making across society and the economy - from housing, education and health care to the labor market, pensions and state investment.
The policy, which went into effect in 1980, was meant to last only 30 years and there are now numerous exceptions to it. But it still applies to about 63 percent of the population.
Peng's push for reform is buttressed by evidence from two-child pilot programs in four regions of the country. In none of them has their been a surge in births.
Numerous studies have shown the detrimental effects of the one-child policy. China's labor force, at about 930 million, will start declining in 2025 at a rate of about 10 million a year, projections show. Meanwhile, its elderly population will hit 360 million by 2030, from about 200 million today.
A skewed gender ratio is another consequence.
Like most Asian nations, China has a traditional bias for sons. Many families abort female fetuses or abandon baby girls to ensure their only child is a son. About 118 boys are born for every 100 girls, against a global average of 103 to 107.
Family planning officials have been known to compel women to have abortions to meet birth-rate targets. Some cases have sparked national fury, such as when a woman in inland Shaanxi province was forced to abort her 7-month pregnancy last year.
Song became interested in the issue of population control during his years as a Moscow-trained missile scientist.
"When I was thinking about this, I took Malthus's book to research the study of population," Song said in a 2005 interview with China Youth Magazine, referring to the English writer Thomas Malthus, who predicted in the 18th century that population growth would outstrip food production.
Song was a protege of Qian Xuesen, a science adviser to former Chinese leaders Mao Zedong and Zhou Enlai. During the 1966-76 Cultural Revolution, Song was among scientists sent by Zhou to a remote northwest province for their protection.
Those ties to the party's founding members give Song clout with today's leaders that few scholars or bureaucrats can match.
"His influence comes from the more direct and open channels of communication (he has) with the central government," said Li Jianmin, a population professor in Nankai University.
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In 2011, in an essay prepared for the Chinese Journal of Population Science but never published, Song described concerns over China's ageing population as "an unfounded worry".
He forecast that China's population, unchecked, would balloon to 2.2 billion in a century, according to a copy of the essay obtained by Reuters. He concluded that zero population growth was "the ultimate goal of human society".
The Chinese Academy of Social Sciences, a government think tank which publishes the journal, did not publish the essay after academics criticized it, according to a scholar familiar with the discussions surrounding the decision not to publish. A representative of the journal could not be reached for comment.
In the copy of a published essay Song mailed to Reuters, he said that abandoning the one-child policy would result in grain shortages of 150 million tons a year.
Opposition From the Provinces
It is far from clear that radical reform of the one-child policy will win the ideological battle in Beijing, despite Song now representing a minority view among demographers in China.
A policy miscalculation in the world's most populous nation carries enormous risks.
During his career, President Xi has stressed that the population should be controlled. And many officials in China's most heavily populated provinces - such as Henan and Shandong - believe the one-child policy is still necessary.
A senior Family Planning Commission official said he did not expect any decision before June due to the restructuring of the commission.
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Many scholars and former family planning officials believe Xi will have no choice but to move to a two-child policy.
The possibility of such a move is already under discussion now in Beijing, said Tian Xueyuan, a retired family planning scholar who worked with Song more than 30 years ago to draft the original one-child policy but who now supports reform.
"This situation cannot remain unchanged," Tian said. "As such there's reason, a need and a possibility that there will be an appropriate adjustment to the policy."