The 38-cover restaurant with 40-cover terrace will open in the Duke of Westminster's former stables, alongside the main 38-bedroom hotel in April.
It will be overseen by Andre Garrett, who joined Cliveden as executive chef in 2013 to open his eponymous fine-dining restaurant and serve a mixture of classic American and British dishes in homage to its diverse owners and residents.
The name The Astor Grill is a reference to the Astor family who owned the house from the early 1900s. William Waldorf Astor, America’s richest citizen, then gave the house to his son and daughter-in-law Nancy Astor in 1906 and Cliveden became a social hub for famous guests such as Charlie Chaplin, George Bernard Shaw and Winston Churchill.
Cliveden's current restaurant Andre Garret at Cliveden is open for lunch and dinner daily and offers an a la carte and tasting menus for hotel residents and non-residents.