The six-year-old appeared alongside his mother Princess Kate and his older siblings Prince George and Princess Charlotte, dancing in front of the crowd.
Britain had put on a display of birthday pageantry for King Charles III in a military parade that marked the Princess of Wales’ first public appearance since her cancer diagnosis early this year.
King jokes with Beckham at star-studded awards
Prince Louis took the opportunity to make light of the event by displaying a set of moves, making Kate smile.
The youngster was quickly pulled into line by his sister Charlotte who appeared to tell him to “stop”.
The prince is known for his playful antics and was also spotted yawning and scrunching his face during a flyby of military aircraft to cap ceremonies marking the monarch’s official birthday.