Republican presidential candidate Marco Rubio denounced China Friday for its new two-child policy, calling it "indefensible and inhumane." The Florida senator tweeted his thoughts one day after China announced it would discontinue its one-child policy and allow couples to have two children.

Rubio was unimpressed by the change. "China's new two-child policy is as indefensible and inhumane as a one child policy," he posted on Twitter. China, the world's most populous country with about 1.4 billion people, introduced the one-child policy in 1979 to slow population growth. Violators were subject to punitive measures, including "fines and the loss of employment to forced abortions," the BBC reported. But as China's population became older, pressure grew to change the policy, in part to help spark economic growth.

Rubio included in his tweet a link to a post on the anti-abortion In the article, Rubio was quoted as saying the one-child policy had caused forced abortions and human rights abuses against girls.

"For over three decades, China’s barbaric One-Child Policy has condemned approximately 37 million Chinese girls – who the policy deemed as unwanted or ‘surplus’ – to abortion, infanticide, abandonment and human trafficking. It has resulted in an unprecedented gender imbalance that will have lasting consequences," the senator told LifeNews. "While the decision to allow Chinese couples to have two children is a modest improvement, the policy is still repressive. The fact remains that when couples conceive a third child, the Chinese government will force them to eliminate him or her, by any means necessary."

Under the one-child policy, China has had exceptionally low birth rates. The country accounts for 19 percent of the world's population but just 12 percent of its annual births, and the number of women age 24-29 -- prime child-bearing years in the country -- is expected to fall 40 percent in the next decade, according to China's the Paper. The policy was loosened in recent years, but reports of human rights violations for families, especially those that wanted to have a son, had been frequent. Some have questioned how much effect the policy change will have.

"A big question going forward is 'are they going to use the same tools to keep it at two as they used for one?' which were quite abusive and in effect were human-rights violations, particularly in rural areas," Richard Bush, director of the Center for East Asia Policy Studies at the Brookings Institution, told U.S. News & World Report. "Coercing pregnant women into abortions if they'd already had one kid, early on forcing them to have sterilizations at least in some parts of China. It was really nasty. Over time, as there was more prosperity, people were more willing and able to pay the fines that were charged, but this will help get the state out of the bedroom up to a point."

Rubio is a father of four himself: Amanda, Daniella, Anthony and Dominic. Coming off a strong performance in this week's primary debate, he now sits at third in national Republican polls, according to the Real Clear Politics average of polls. Rubio has said he would ban abortion under any circumstances, without exceptions for rape or when the mother's life is in danger, as Reuters reported in August.