"I do not believe, and I know this is a horrible thing to say, but I do not believe that the president loves America," Giuliani reportedly said at a private New York dinner for Wisconsin Gov. Scott Walker (R). "He doesn't love you. And he doesn't love me. He wasn't brought up the way you were brought up and I was brought up through love of this country."
Asked about the matter during a flight aboard Air Force One to Chicago, a White House spokesman partially agreed with Giuliani's assessment -- of his own remarks. "It was a horrible thing to say," deputy press secretary Eric Schultz said, according to a pool report.
Schultz further jabbed at the onetime presidential hopeful by noting that Giuliani had tested the line during his "fleeting 2007 run for the presidency."
Democrats have also denounced Giuliani's comments as offensive and called on Walker and the rest of the potential 2016 GOP presidential field to do the same. "I rarely agreed with President Bush, but I never questioned his love for our country," said Democratic National Committee Chair Debbie Wasserman Schultz.
Walker, who was in the room while Giuliani was speaking, responded Thursday morning. "The mayor can speak for himself. I'm not going to comment on what the president thinks or not," Walker said. "I'm in New York. I'm used to people saying things that are aggressive."
Louisiana Gov. Bobby Jindal (R), another possible 2016 candidate, came to Giuliani's defense. "The gist of what Mayor Giuliani said -- that the President has shown himself to be completely unable to speak the truth about the nature of the threats from these ISIS terrorists -- is true," Jindal said in a statement.
Sen. Marco Rubio (R-Fla.) declined to go that far. He told reporters in New Hampshire that he had "no doubt" that Obama loves America, "but I just think his policies are bad for our nation."
Giuliani expanded his criticism Thursday by suggesting that Obama lacks a certain fondness for "Western civilization."
"When I see Christians slaughtered and I don't see the American president standing up for them as Christians, when I see Jews slaughtered and I don't see him standing up of them as Jews, I wonder if my criticism about his love of America doesn't extend to a criticism of a love of Western civilization," Giuliani said in an interview with WABC in New York.