U.S. Vice President Joe Biden is facing sharp criticism from conservatives politicians and commentators over a remark made during his recent visit to China that appeared to condone the country's one-child policy.

Several candidates for the Republican Party presidential nomination — including former ambassador to China Jon Huntsman — have condemned the remark, saying the policy is responsible for forced sterilizations and abortions.

In a speech last week at Chengdu University in southwestern China, Mr. Biden argued that the policy restricting most Chinese families to only one child is economically unsustainable. But the vice president, who is a Roman Catholic, said he fully understands the reasons for the policy and was “not second-guessing” it.

Mr. Biden's office responded to the criticism with a formal statement Tuesday saying the vice president strongly opposes all aspects of China's coercive birth limitation policies. It said he finds such practices as forced abortion and sterilization “repugnant.”