London's Oxford Street and Regent Street Christmas lights have been switched on at precisely the same time.
Actor Jim Carrey flicked the switch on the Oxford Street lights, themed around the work of Charles Dickens' A Christmas Carol on Wednesday evening.
At the same time, British actor Colin Firth switched on the lights in nearby Regent Street.
Meanwhile fellow British actor Bob Hoskins led the city's celebrations at St Paul's Cathedral.
Revellers secured the world record for the most people singing a Christmas carol, led by Andrea Bocelli and the St Paul's Cathedral Choir live on big screens in Oxford Circus.
The switch-on of the lights was due to be followed the world premiere of Disney's film A Christmas Carol, which stars Carrey, Firth and Hoskins, at three London cinemas.
In 2008, the switch was flicked for the Regent Street lights on 6 November and the Oxford Street lights on 12 November.
This year's lights will be lit after dark each day until 6 January 2010.