A Trump administration physicist — who is pushing to create a panel with the purpose of debunking climate change — has said in the past that he thinks the “demonization” of carbon dioxide is similar to the way Jewish people were treated under Adolf Hitler in Nazi Germany.

The comments, from 2014, made the rounds on Tuesday after New York Times published an article on the Trump administration’s efforts to push back against efforts to combat climate change.

“The demonization of carbon dioxide is just like the demonization of the poor Jews under Hitler,” William Happer, a former Princeton physicist who serves on Trump’s National Security Council as Trump’s deputy assistant for emerging technologies, told CNBC in 2014.

Happer has pushed to create a climate review panel that would essentially question the conclusions reached by a widely accepted methodology for assessing climate change. It’s just one portion of the administration’s broader effort to dismantle former President Barack Obama’s efforts to cut back on greenhouse-gas emissions.

Most recently, Trump’s head of the United States Geological Survey, James Reilly, has directed that all assessments conducted by his office only make projections on the effects of climate change through 2040. Previously the office made projections through the end of the century.

Editor’s note: This article has been updated to reflect that William Happer’s comments were made in 2014.