President Obama shook hands with now-controversial rapper PSY just days after his anti-American past was unearthed.

It was revealed Friday that the YouTube sensation sang about killing American soldiers “slowly and painfully” in 2004, causing shock and outrage to his millions of fans.

The two met last night at the 31st annual “Christmas in Washington” charity concert last night during which PSY and his dancers performed his popular “Gangnam Style” dance, which mimics riding a horse.

The president was radio silent about PSY during his brief remarks after the concert.

According toUSA Today, the president gave shout-outs to host Conan O’Brien, Ross and “all the other talented folks on this stage” — but did not mention the South Korean rapper. Demi Lovato, “American Idol” winner Scotty McCreery and Megan Hilty also performed.

His performance came just days after the rapper apologized for using what he called “inflammatory and inappropriate language” during anti-US protests at concerts in 2002 and 2004.

The “Christmas in Washington” concert benefits Children’s National Medical Center. Before the show, Obama was accompanied by his wife, Michelle, and daughters, Sasha and Malia, as he presented a basket of books to four former patients of the center, who were dressed as elves.

The concert is scheduled to air Dec. 21 on TNT.

WITH AP