Raffles Hotels and Resorts will open its flagship London property on 29 September, complete with the capital’s first-ever Guerlain-branded spa.

The 27,000sq ft spa at Raffles London at The OWO will sit at the heart of the landmark Grade II* listed former Old War Office on Whitehall, completed in 1906 by British architect William Young.

The historic building was formerly the site of the original Palace of Whitehall, home to Henry VIII and other monarchs. It also witnessed world-shaping events while influential political leaders – including Winston Churchill – held office.

Designed by interior design studio Goddard Littlefair, the luxury spa and wellness space will span four levels.

Facilities will include nine treatment rooms fitted with Gharieni treatment beds, a selection of indoor pools, a sauna, a barbers and salon, beauty treatment spaces, a gym and a Guerlain boutique, in addition to a separate VIP area and two couples suites.

To mark the new opening, Guerlain has devised three exclusive facial and body treatments to "capture the essence of England". These include the Royal Glow Tech Facial (90 minutes // £350, US$449, €405), the Spirit of London (90 minutes // £300, US$385, €347) and Coastal Escape (60 minutes // £210, US$270, €243).

Véronique Courtois, CEO of Guerlain, said the new flagship in London is set to be a "world-class spa".

“To introduce Guerlain to London will be a truly special moment for us, especially in a space with such incredible heritage, countless stories and such a meaningful history.”

Now operating more than 40 branded spas and institutes worldwide, the Guerlain company was founded in 1828 and ran as a family business up until 1994 when it was acquired by the luxury goods conglomerate Möet Hennessy Louis Vuitton (LVMH).

Open to hotel guests, residents of The OWO Residences by Raffles, spa members and day guests, the spa will join the hotel’s 120 rooms and suites, 85 branded residences and 11 destination restaurants and bars.

Spa and wellness industry veteran Robert Jeffers has been appointed to helm the spa as director of wellbeing.

In addition, movement specialistPillar Wellbeing will launch a members’ health club and oversee the training and health programming at Raffles London.

The active wellness spaces, driven by Pillar, will comprise a gym and yoga studio, juice bar and a swimming pool complete with a vitality pool, saunas and steamrooms.

Founded by elite performance coach Harry Jameson, Pillar will offer a distinct service that places equal emphasis on movement, recovery and nutrition. Dedicated programmes for members, delivered by expert trainers, will focus on strength and stress relief.

In addition, therapists will offer a range of recovery experiences with a tailored nutritional offering created by Pillar chef Joey O’Hare, available from the ground floor PillarKitchen.