Jimmy Kimmel responds to Bill Cassidy and Chris Christie.

Comedian Jimmy Kimmel is taking the Republican Party to task over the Graham-Cassidy healthcare bill, the party’s latest attempt to strike down the Affordable Care Act. On Wednesday night, Kimmel’s monologue took aim at the bill’s co-primary sponsor, Republican Senator Bill Cassidy, who had promised Kimmel earlier this year that he wouldn’t propose any bills that allow insurance companies to turn away people with pre-existing conditions or put an annual or lifetime cap on medical care costs.

But his new plan definitely allows for those things to happen and also cuts massive health insurance funding to 34 states.

On Jimmy Kimmel Live!, Kimmel said that Cassidy “either doesn’t understand his own bill, or he lied to me, it’s as simple as that.”

In the meantime, Cassidy spent his Wednesday morning defending himself and his bill after Kimmel first tore into him on Tuesday night. Cassidy attempted to argue that Kimmel just didn’t understand the bill, leading Kimmel to ask whether the bit he didn’t understand was:

“. . .the part where the American College of Physicians, the American Academy of Pediatrics, the American Hosptial Association, the American Cancer Society, the American Diabetes Association, the American Heart Association, Lung Association, Arthritis Foundation, Cystic Fibrosis, ALS, the National Multiple Sclerosis Society, and the March of Dimes, among many others, all vehemently oppose your bill. Which part of that am I not understanding?”

Kimmel is right: Scores of hospitals and doctors have spoken out against the Graham-Cassidy Amendment, saying that it would disrupt healthcare for millions while causing harm to the most vulnerable patients. The American Medical Association has said that it “violates the precept of ‘first do no harm,’” a guiding oath among medical professionals. The American Hospital Association, for its part, says that the new proposal would “erode key protections for patients and consumers and does nothing to stabilize the insurance market now or in the long term.”

Republicans in the Senate hope to pass the bill before September 30, which is the last day where lawmakers can pass a bill with a Republican majority and no Democratic votes. Kimmel is unlikely to stop speaking out against the bill anytime soon: The late-night host has been very vocal about the importance of affordable healthcare since May, after he revealed that his own son was born with a heart defect and required a series of expensive surgeries.

“The reason I’m talking about this is that my son had to have an open heart surgery, and has to have two more,” Kimmel explained Wednesday night, “and because of that, I learned that there are kids with no insurance in the same situation.”