The London municipal building has been wrapped by Icon with a 200sqm display.
"City Hall has today (23 August) become London's billboard for the 2018 World Cup Bid sporting a giant red and white banner created by London based branding agency Icon," said London mayor Boris Johnson.
"The boys might not have brought the World Cup home this summer, but we're right on track to bring the tournament here in 2018. In 100 days time we could all be World Cup winners and I believe that nowhere in the world could host a better World Cup than England for 2018, so wherever you are in the country, I'm urging you to back the bid."
A Fifa delegation has headed to London today to take a look at some facilities and see how the bid is progressing.
David Hornby, once of Visit London, now of a variety of firms including Jamie Oliver’s Fabulous Feasts and Smyle, will advise on London 2018 live events.
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