There were plans to turn the mansion into a museum; the property was to be subdivided and individual dwellings built, including the adjacent mansion built by the architect Jean Walter in 1924. However, Gaston Doumergue learned of the plans and decided to make it the headquarters of the President of the Council of Ministers ("Président du Conseil"), as the position of head of government was known under the Third Republic. The architect Paul Bigot took the necessary steps and, in 1935, Pierre Étienne Flandin became the first new occupant.