Justin Bieber shakes hands with President Obama as he performs at the 2011 Christmas in Washington at the National Building Museum on Sunday night (December 11) in Washington, D.C.

The 17-year-old musician (in Dolce&Gabbana) landed in the nation’s capital just a few days ago with girlfriend Selena Gomez for the big event, which will be broadcast on TNT this coming weekend.

“Feeling good. Just had some fun at rehearsals and now we r ready. Time to sing for the President. #canadianrepresenter,” Justin tweeted just before the audience filled into the space.

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Justin added, “Great night! President Obama is one cool Prez. He told me he was “chillin.” #PresidentialSWAG”

This is the second time Justin has performed at the annual event. This year he sang “Mistletoe” and “Away in a Manger” for the closing medley.

The 2011 Christmas in Washington will air on Friday, December 16th @ 8PM ET/PT on TNT.

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