The agency, which will open its doors at the end of this month, will be the first launch in a proposed micro network from the Havas-owned BETC, which will look to build on the success of the 600-strong French agency.
Its offices will be based in Golden Square, and the agency will aim to grow a client list of both global and UK-specific advertisers.
Charlton and Dawson, who will both take a minority stake in the business, have previously worked together at Bartle Bogle Hegarty, where they oversaw the Johnnie Walker account.
Most recently Charlton, who was the managing director of TBWA\London between 2007 and 2008, was the president of the independent creative agency Modernista!
Dawson joins BETC from DDB, where he was the global chief creative officer on Philips. During his time on the account he oversaw the "Carousel" and "Parallel Lines" campaigns, both of which won Cannes Grand Prix.
Prior to DDB, Dawson held senior creative roles at TBWA\London and Ogilvy & Mather.
BETC Paris was established 17 years ago by Remi Babinet, Mercedes Erra and Eric Tong Cuong. The agency now has 68 clients including Peugeot, Air France, Canal+ and Disneyland, and in 2010 was ranked 2nd in The Gunn Report, thanks in part to its renowned "Rollerbabies" campaign for Evian.
Babinet said: "London is a reference in terms of quality, intelligence and efficiency in design and advertising. Setting up an agency there is very important to us."