Prince William too had a blast at the party to celebrate the wedding of Guy Pelly as he took to the microphone in full morning dress and belted out "Shout" from the stage.
The Duke of Cambridge was the "life and soul of the party" as he entertained the crowd with his singing and dancing, according to onlookers.
Prince Harry, newly single after his split from Cressida Bonas, 25, showed off his moves exuberantly but was "just having fun" and did not appear to have found a new love interest among the women at the party, The Telegraph reported.
"They were holding people up in the air and passing them around like they were flying. I've been doing this 50 years and I ain't ever seen anything like this. These guys know how to party," Church said.
The band finished off with "Don't Stop Believing" after 1am. But the Princes resisted the temptation to join a group of guests including their cousin Princess Eugenie, and friend Tom "Skippy" Inskip, at a bar in the Peabody Hotel where the party went on until 3am.
At the ceremony itself Prince Harry had looked somewhat weary following a US trip that had already included partying at a nightclub in Miami and a trip to Graceland.
While female guests looked at him, and tried to catch his eye, he instead spoke with a young flower girl, and was also seen with a woman with a young baby, it said.
