Tourists at Buckingham Palace were treated to a surprise when more than 100 dancers emerged from the crowds to take part in a royal 'flashmob'.
Visitors waiting for the Changing the Guard were taken aback when dancers rose from the Queen Victoria memorial and began slapping their knees and clapping their hands.
Starting with just four dancers, the group quickly grew, with performers emerging from all corners of the crowd as bystanders looked both delighted and bemused.
The dancers, mainly students from the University of East London, clicked their fingers, stamped their feet and shook their bodies to a mix of tunes including Queen's We Will Rock You.
Performing fast arm movements known as waacking, the group got increasingly bigger as they performed a series of formations in front of the Palace.
The flashmob was secretly planned by Buckingham Palace to mark a royal reception to honour young people in the performing arts.
University of East London dance student Lucy Sam, 19, from Birmingham, said the choreography had been inspired by the royal wedding and explored romance using urban dance techniques.
"Our theme was Romeo and Juliet because of the royal wedding. It's just to celebrate Kate and William and their love," she said.
Sightseer Tom Accor, 22, from Turin, Italy, said the cameras and mounting anticipation had made him think "something big" was about to happen.
"I saw the cameras before and thought it would be the Queen or Kate and William arriving but this was very surprising," he said.