Robbie Williams launches London's Christmas

Leona Lewis and boyband Lawson warmed up the 20,000-strong crowd with performances at the Oxford Street event, held annually to light up the shopping Mecca, reported Daily Star.

Then Williams took to the stage to sing before flicking the switch to turn on the mile-long display.

"Tonight's event was incredible - the Oxford Street crowds were amazing, and it was fantastic being part of the celebrations," said the singer.