WASHINGTON — Sen. Bill Cassidy is pressing President Donald Trump’s nominee to lead the Food and Drug Administration to publicly reject the president’s false claim that the measles vaccine is “quite lethal.” Cassidy, a Republican physician from Louisiana who chairs the Senate Health, Education, Labor and Pensions Committee, said Sunday that Dr. Heidi Overton must address the claim during her confirmation hearing later this week. “I need to hear that she understands that calling the measles vaccine lethal is absurd, and we need radical honesty,” Cassidy said on CBS’ “Face the Nation.” The measles vaccine is part of the measles, mumps and rubella, or MMR, vaccine. Trump has also linked the vaccine to autism, despite extensive scientific evidence finding no connection between vaccines and autism. Last month, Overton appeared with Trump in the Oval Office as he made those claims. Trump also signed an executive order changing the recommended schedule for childhood vaccinations. Cassidy previously called the executive order “nonsensical” and said Overton’s involvement in the announcement was “almost disqualifying.” On Sunday, he said the nominee should explain whether she would challenge misinformation from the president if confirmed to run the FDA. “We should have a common voice of radical honesty of trying to help the American people understand what is safe,” Cassidy said. “And if the president calls it lethal, then where are you getting your information, Mr. President?” Cassidy pointed to Dr. Nicole Saphier, Trump’s nominee for surgeon general, who told senators during her confirmation hearing last week that vaccines are safe. Cassidy said her willingness to make that statement earned his support. “When somebody is willing to be honest to the American people and say that vaccines are safe, you should be taking it,” Cassidy said, adding that the consequences of avoiding vaccines can include death. The confrontation puts a Republican committee chair in the position of demanding a clear public break with the president on a major public-health issue. It also comes after Cassidy lost Louisiana’s Republican Senate primary in May. He finished behind Trump-endorsed Rep. Julia Letlow and state Treasurer John Fleming, ending his campaign for reelection. Cassidy’s disagreements with Trump have persisted for years, including his vote to convict Trump in an impeachment trial. The Senate health committee is scheduled to consider Overton’s FDA nomination Thursday.