Beijing - China said on Tuesday its battle to rein in soaring greenhouse gas emissions has received a boost from an unexpected source - the nation's controversial family-planning policy.
Since its adoption in the late 1970s, the so-called "one-child" policy has averted the births of more than 300 million people, who would have emitted an additional 1,3 billion tons of carbon dioxide per year, a government environment report said.
If true, the figure would represent more than one-fifth of China's current emissions, based on estimated figures released by a Dutch agency last year.
The Netherlands Environmental Assessment Agency said China emitted an estimated 6,2 billion tons of the gas in 2006, which has been blamed for causing global warming.
In its report, the agency said China had likely surpassed the United States as the world's biggest contributor to climate change.
China's family planning policy began in the late 1970s as a way to prevent the world's largest population - now at approximately 1,3 billion people - from exceeding the country's capacity to feed it.
Generally, urban families can have one child, while exceptions are made for rural families and minority groups.
The government has said previously that the policy has averted as many as 400 million births. It was unclear why the government changed that number.
However, the rules have been blamed for contributing to a large gender imbalance in favour of males.
It has also been blamed for resulting in forced sterilisations and late-term abortions in the name of enforcement.