Fire engulfed the top floor of Paris's Ritz Carlton hotel on Tuesday, burning out of control for hours in one of the city's highest developments.

The blaze began early in the day at the luxury hotel where Diana, Princess of Wales, spent her final hours before the car crash in which she died.

The hotel has been closed for renovations for three years and was expected to reopen in March, restored to the grandeur that drew the likes of Frederic Chopin, Coco Chanel and Ernest Hemingway.

Police in the French capital said there were no known casualties.

Fire trucks and police blocked off the Place Vendome at the height of the morning rush-hour, and firefighters on cranes sprayed the flames to try to bring the blaze under control.

Place Vendome is also home to numerous high-end jewellery stores and boutiques, as well as France's Justice Ministry.

Fire Captain Yvon Bot said the blaze, which began in the roof, was unusually difficult to access and control.