Republican presidential candidate Mitt Romney, courting conservatives who still regard him with suspicion, denounced China's "one-child" policy on Friday as "barbaric."

"I will cut off funding for the United Nations Population Fund, which supports Chinas barbaric 'One Child' policy," Romney said in a speech to the Conservative Political Action Conference (CPAC) in Washington.

State media in China, the world's most populous country with more than 1.3 billion people, said in October that Beijing would maintain the policy, which punishes couples who have more than one child.

China's one-child policy was introduced in 1979 to curb population growth, but has become increasingly unpopular as the country's population ages.

Critics blame the policy for gender imbalances -- sex-specific abortions are common and female infanticide and the abandoning of baby girls have also been reported -- and some say it is enforced with forced abortions and sterilization.

The policy also puts huge pressure on only children to support their parents and two sets of grandparents.

Policy violations usually result in hefty fines and a cut back in social services, although some ethnic minorities and farmers whose first child is a girl are excluded from the restriction.

In August, Romney had denounced the policy as "gruesome and barbaric," and US Vice President Joe Biden called it "repugnant."