President Trump on Monday slammed Sen. John McCain for his opposition to several Republican proposals to repeal Obamacare, including the latest Graham-Cassidy plan.

"I mean you look at McCain, what McCain has done is a tremendous slap in the face of the Republican party. Tremendous. He was good to go all the way up until 1 or 2 o'clock in the morning when he voted no," Mr. Trump said on "The Rick & Bubba Show," a radio program.

McCain announced in a statement Friday that he opposes the last-ditch Graham-Cassidy effort because it hadn't gone through regular order. He helped deliver the deciding blow to GOP leadership's last effort to repeal Obamacare at the end of July, shocking the political world by turning his thumb down in a "no" vote. McCain, who was diagnosed with an aggressive form of brain cancer over the summer, delivered a dramatic floor speech the day he returned to the Senate in which he urged members of his own party to return to "regular order" and to seek bipartisan solutions.

The president also said that Republican Senate candidate Roy Moore will have a "hard time" getting elected during the 2018 midterm election next year if he wins the GOP primary in Alabama on Tuesday. Mr. Trump has endorsed incumbent Sen. Luther Strange and rallied in support of him on Friday.