Former Republican Indiana senator Richard Lugar, who served as chairman of the Senate Foreign Relations Committee, told E&E News he thinks President Donald Trump should keep the U.S. in the Paris Climate Agreement.

“This is going to be extremely important for the United States to participate in and to try to persuade others to do so, or we’re going to have great losses in our country as waters come up over our coast or in the interior of our country, rivers overflow residential areas,” Lugar said. He called the Paris Agreement necessary to prevent “genuine global warming,” while acknowledging the continued “debate among the naysayers who say the science community is all wrong on this.”

“Other countries will probably still maintain a strong interest in the Paris Agreement, or more importantly in control of CO2 around the world,” he said. “The Chinese in particular, with their cities engulfed by horrible pollution day in and day out, are already suffering.”

While serving in the Senate, Lugar acknowledged human activity caused climate change and supported measures to reduce carbon emissions. He lost a primary challenge in 2012 after serving 36 years.