Londoners are invited to join City Hall staff and representatives from businesses, community organisations and faith groups at this Christmas celebration.
Readings will be given by the Mayor of London Boris Johnson and the chair of the London Assembly Jennette Arnold, along with Natasha Baker, who won two gold medals in dressage at the Paralympics, and Olympic rower Alex Partridge, who took bronze in the men's eight event at the Olympic Games.
Also giving readings will be Team London ambassador Kiran Kaur and gamesmaker Louise Cheung. Kiran Kaur will read the poem 'I Am', which was written by ten year-olds Paige Wilson, Heather Murray and Luke James, who all attend Roding Primary School in Dagenham. Their poem was shortlisted in the Highly Commended category from over 2,000 entries in the Mayor's London 2012 Poetry Competition.
There will also be special performances by Urban Voices Collective, who took part in the closing ceremony of the Olympic Games and St Catherine School Girls' Choir from Bexleyheath.
The blessing will be given by the Bishop of Southwark, Rt Revd Christopher Chessun.
To be sure of a seat, members of the congregation are advised to arrive early.