The new bar, located on Great Portland Street, is over 2000sq.ft in size and will open mid-November.
It will list at least 100 Champagnes and sparkling wines by the bottle and more than 25 by the glass, with prices starting at £9 a glass.
Flûte Bar & Lounge London will be the fourth in the group. It has two locations in Manhattan - including Flûte Midtown, winner of the Nightclub & Bar Award 2010 for Wine Bar of the Year - and another in Paris.
“Flûte will combine an inimitable New York atmosphere - one that's neither affected or outrageously expensive - with an amazing Champagne selection and excellent service,” said owner Rousseau.
“We are simply offering what we feel is a unique proposition that we hope will be embraced by Londoners and visitors alike.”
Unique inspiration
Accompanying the drinks selection will be a menu of light bites, spearheaded by a spring roll bar serving 20 different variations. Rousseau revealed his unique inspiration behind this idea.
“My stepmother, Shu Rousseau, is from Saigon, hence the spring rolls. They are delicious, healthy and, most important of all, the perfect accompaniment to champagne!”
The venue will also present a full schedule of weekly and monthly events, including live jazz, DJs, food pairings and regular champagne tasting classes. Music at Flûte will feature a playlist specially mixed by some of New York's top DJs.
Rousseau, who founded Flûte in 1997, said that while further expansion throughout the UK is a possibility, it will depend on the success of the new bar.
“We are not the kind of company to brag about opening branches all over the UK. Let's see what happens in London first, strive to build the best place possible and only then think about expanding the concept.”