Bieber and Hudson perform for Obama
Justin Bieber, Cee Lo Green and Jennifer Hudson were among the stars performing in front of US president Barack Obama at the 30th annual Christmas in Washington concert.
President Obama, his wife Michelle, daughters Malia and Sasha, and mother-in-law Marian Robinson attended the concert to benefit the Children's National Medical Centre.
The concert of Christmas carols and songs, which took place at the National Building Museum, was hosted by comedian Conan O'Brien.
Before the concert, the Obamas greeted patients of the children's medical centre dressed as elves and presented them with a basket of children's books. The US president playfully struggled to lift the basket and asked the elves to help him place it under a Christmas tree.
Other entertainers included the United States Naval Academy Glee Club, Washington Youth Choir, American Family Choir, United States Army Band Herald Trumpets, Ian Fraser and the Christmas in Washington Orchestra.
The concert will air on American TV channel TNT on Friday.