In July 1936 , de Valera wrote to King Edward in London saying that he planned to introduce a new constitution . In July 1936 , de Valera as constitutionally the King 's Irish Prime Minister , wrote to King Edward in London indicating that he planned to introduce a new constitution , the central part of which was to be the creation of an office de Valera provisionally intended to call President of SaorstÃ t Ã ireann , which would replace the governor-generalship .