All couples in China might be allowed to have a second child in the next few years with the relaxation of the family planning policy, population experts say.

Currently, most couples in urban areas may have a second child if at least one of the two has no siblings, and couples in rural areas can have a second child if the first one is a girl.

Most scholars in China agree with further relaxing the family planning policy so that all couples can have two children, if they want, "and the focus of disputes on the issue is when and in what forms the policy will be carried out", said Yuan Xin, a professor of population studies at Nankai University in Tianjin.

"In my opinion, all couples will be allowed to have two children after two or three years, following the current transitional period," Yuan said.

Family planning polices are a concern for the entire population, and changes should be implemented cautiously, he said.

After the National People's Congress, China's top legislature, adopted a proposal in 2013 to allow couples to have a second child if one of the two has no sibling, more than 1 million such couples had registered to do so by the end of last year, according to the National Health and Family Planning Commission.

"It is a transitional policy, and it has some incentive to stimulate population growth in China, but the incentive will be diminished over the next few years," Yuan said. "And then it will be the time for a policy that allows two children universally."

Yang Juhua, a professor at the population development studies center at Renmin University of China, said a more relaxed family planning policy makes sense, considering the very low fertility rate and a rapidly aging population.

"I think there will be no question that all couples across the country will be allowed to have a second child during the 13th Five-Year Plan period (2016-2020)," she said.

Zhai Zhenwu, head of China Population Association, also has said that family planning policies will be further relaxed, according to a report in Southern Metropolis Daily on Thursday.

China adopted a strict one-child family planning policy in the 1970s. The policy has been gradually relaxed since the late 1990s, and since 2011 all couples have been allowed to have a second baby if both of them have no siblings.

Song Shuli, spokeswoman for the National Health and Family Planning Commission, the top government department in charge of population policies in China, said at a news conference in April that further relaxation of the policy is expected. But China must be mindful of the burden a large population places on resources, the environment and social development, she said.

Those who will get the most benefit from the policy change would be government employees, who are more restricted by the policies than ordinary people, Yang said.