This could be trouble. Just one day before he's scheduled to perform 'Gangnam Style' for President Obama at the Christmas in Washington DC 2012 concert, Korean rapper Psy is in hot water after an unconfirmed report surfaced suggesting that in 2004 he performed at an anti-American concert in Seoul, South Korea and rapped lyrics about "killing those f---ing Yankees." revealed the news, which was first reported in a CNN iReport in October but was never picked up by the media. According to the unsubstantiated report, Psy took part in a group performance of the song 'Dear American' by rock group N.EX.T., which included lyrics that translate as, "Kill those f---ing Yankees who have been torturing Iraqi captives / Kill those f---ing Yankees who ordered them to torture / Kill their daughters, mothers, daughters-in-law, and fathers / Kill them all slowly and painfully."

Before the public immediately launches a Dixie Chicks-style boycott against Psy, the Busanhaps article attempts to put Psy's words in context. First, he wasn't performing his own song. Second, anti-American sentiment in Korea at the time was very high after the U.S. military invaded Iraq and a Korean missionary was murdered by Iraqi militants. Then there's the matter of the source of the news. CNN iReports are citizen-submitted blog posts that are not fact-checked.

Will any of those caveats matter? Not to some outraged Americans and defenders of the military, who have already started a petition calling on the president to refuse to allow Psy to perform at the DC concert because of the inflammatory language he may once have used.

We're eager to hear from Psy on this matter, but so far he hasn't commented. The White House has only 24 hours to decide whether to rescind Psy's invitation, since the Christmas in Washington concert is scheduled for Saturday, Dec. 8, though it won't air until Dec. 21 on TNT.

UPDATE: Psy released an apology, which you can read in its entirety here. Here's a clip: "While it's important we express our opinions, I deeply regret the inflammatory and inappropriate language I used to do so. In my music I try to give people a release, a reason to smile. I have learned that though music, our universal language we can all come together as a culture of humanity and I hope that you will accept my apology."

Watch the Psy 'Gangnam Style' Video

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