Sen. Bernie Sanders (I-Vt.) has came under fire from conservatives on social media Thursday after he said he would be open to discussing population control as a means to combat climate change.

The presidential candidate made the comments on Wednesday at a climate town hall on CNN after he was asked by an attendee about rising populations and how the planet "can not sustain this growth."

The questioner, identified by CNN as a teacher named Martha Readyoff, said that she realized linking population control to climate was a topic "poisonous for politicians, but it's crucial to face."

"Empowering women and educating everyone on the need to curb population growth seems a reasonable campaign to enact. Would you be courageous enough to discuss this issue and make it a key feature of a plan to address climate catastrophe?"

"Well, Martha, the answer is yes," Sanders said.

"The answer has everything to do with the fact that women in the United States of America, by the way, have a right to control their own bodies, and make reproductive decisions," the senator said to applause from the crowd.

"The Mexico City agreement which denies American aide to those organizations around the world that allow women to have abortions or even get involved in birth control to me is totally absurd," Sanders continued. "So I think, especially in poor countries around the world where women do not necessarily want to have large numbers of babies, and where they can have the opportunity through birth control to control the number of kids they have, is something I very, very strongly support."

The comments quickly sparked outrage from conservative media figures, including CNN host S.E. Cupp, who said Sanders was talking about eugenics when he made the comments.

Eugenics is the science of selective and controlled breeding in an effort to increase human characteristics and traits deemed desirable

Other conservatives voices on social media also criticized the remarks by Sanders, who is a leading contender for the Democratic presidential nomination.

Sanders frequently touts his progressive policies to combat climate change, which has become a top issue for Democratic primary voters. He made Wednesday's remarks during a CNN event on climate change that featured most of the Democratic field.

The Hill has reached out to the Sanders campaign for comment.