WASHINGTON (AP) -- Democrats on Thursday assailed former New York City Mayor Rudy Giuliani for questioning President Barack Obama's love of country, and urged the potential field of Republican presidential candidates to rebuke his comments.

Democratic National Committee chair Debbie Wasserman Schultz said at the start of the DNC's winter meeting that now is the time for Republican leaders to "stop this nonsense."

Giuliani, who sought the 2008 GOP presidential nomination, said at a New York City event on Wednesday night that "I know this is a horrible thing to say, but I do not believe that the president loves America."

Former New York City Mayor Rudy Giuliani. (AP Photo/John Minchillo, File)

"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," Giuliani said, according to Politico.

The questioning of Obama's patriotism brought to mind a familiar conservative criticism during his 2008 and 2012 campaigns that he hasn't been proud enough of the United States. During his presidency, a smaller segment falsely claimed that Obama was not born in the United States but rather in his father's native Kenya.

The private dinner was attended by Wisconsin Gov. Scott Walker, who is considering a 2016 campaign. Giuliani said that "with all our flaws we're the most exceptional country in the world. I'm looking for a presidential candidate who can express that, do that and carry it out."

"And if it's you Scott, I'll endorse you," Giuliani said, addressing Walker. "And if it's somebody else, I'll support somebody else."

Walker, asked about the comments in an interview with CNBC, did not directly address whether he agreed with the former mayor.

"The mayor can speak for himself. I'm not going to comment on whether - what the president thinks or not. He can speak for himself as well," Walker said. "I'll tell you, I love America, and I think there are plenty of people, Democrat, Republican, independent, everywhere in between, who love this country."

Asked about Obama in an interview with Fox News on Thursday, Giuliani said he wasn't "questioning his patriotism. He's a patriot, I'm sure. What I'm saying is, in his rhetoric, I very rarely hear him say the things that I used to hear Ronald Reagan say, the things that I used to hear Bill Clinton say, about how much he loves America."

A spokesman for Kentucky Sen. Rand Paul declined comment and a spokeswoman for former Florida Gov. Jeb Bush had no immediate response. Both are potential Republican presidential candidates.

Wasserman Schultz, a Florida congresswoman, said she often disagreed with former President George W. Bush and Republicans in Congress but never questioned their patriotism. She noted that Arizona Sen. John McCain, during his 2008 presidential campaign, urged fellow Republicans not to question Obama's love of country.

"I would challenge my Republican colleagues and anyone in the Republican party to say, `Enough.' They need to start leading," Wasserman Schultz said.

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