#LondonIsOpen will be promoted at major events in the capital this summer.
Tracy Halliwell, director of business tourism and major events at London & Partners, the promotional company for London, said: "This campaign shows businesses and event organisers that despite the vote to leave the EU, London is still open to everyone and remains one of the best cities for conferences and events."
"With the current drop in the value of the pound, there has never been a better time to take advantage of London's unbeatable value, with its wide variety of venues, accommodation and activities suitable for everyone."
The campaign, built around the idea of London opening its doors to welcome people in, aims to show that the capital is 'creative, international, entrepreneurial and full of opportunities' and that discrimination will not be tolerated.
Business backers of the campaign include Hilton, Merlin Entertainments and Sir Richard Branson.
Artists including Turner Prize winner Jeremy Deller are being invited to interpret #LondonIsOpen, with the resulting work to appear across Transport for London’s network.
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