The palatial former home of Artemis Onassis, who was sister of shipping billionaire Aristotle, is considered one of the grandest and biggest in Grosvenor Square.
The ambassadorial first-floor apartment at No 47 has 5,006sq ft of living space and a 63ft balcony.
On the market for the first time in 28 years and steeped in tales of aristocracy, wealth and glamour, previous guests have included Jackie Kennedy Onassis and her sister, Princess Lee Radziwill.
The magnificent master bedroom suite has his and hers walk-in dressing and bathrooms.
There is also a lavish library, formal dining room and study, all opening on to the balcony overlooking Grosvenor Square. Listed with Wetherell, the price tag’s an eye-watering £25 million.
Aristotle and Jackie Onassis (Getty Images)