Donald Trump, de facto leader of the so-called "birther" movement, called into "The Situation Room" on Tuesday for what quickly became a testy interview with Wolf Blitzer about Trump's continued skepticism over the authenticity of President Obama's Hawaiian birth certificate.

Trump, in Las Vegas to host a fundraiser for Mitt Romney on Tuesday, took issue with Blitzer's introduction and a CNN report that ran before the interview, both of which asserted that Trump, real estate mogul and reality show star, is standing by his birther comments. Trump claimed he agreed to the "Situation Room" interview to talk about jobs, China and OPEC; Blitzer said there were no such ground rules.

"You know that's what I'm here to talk about, and I thought your introduction was highly inappropriate," Trump said. "But that's OK, because I have gotten to know you over the years."

Blitzer then presented Trump with Obama's birth announcements that ran in Hawaiian newspapers.

"Can you stop defending Obama?" Trump stammered.

More from the heated exchange via CNN's transcript:

BLITZER: Donald, you're beginning to sound a little ridiculous, I have to tell you. TRUMP: You are, Wolf. Let me tell you something, I think you sound ridiculous, and if you'd ask me a question and let me answer it. BLITZER: Here's the question, did the conspiracy start in 1961 where the Honolulu Star-Bulletin and the Advertiser contemporaneously published announcements that he was born in Hawaii? TRUMP: Many people put those announcements in because they wanted to get the benefit because of getting so-called born in this country. Many people did it. It was something done by many people even though they weren't born in the country. You know and I know it.

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