An initial bid was rejected by a single vote in December 2015 after councillors decided the plans, which included two six-storey extensions, would damage the setting of the A-listed neoclassical building on the flanks of Calton Hill.

Under new plans lodged by Hoskins Architects, the £70 million project will now have 127 rooms, 20 fewer than originally envisaged.

Co-investors Duddingston House Properties, Urbanist Hotels and Oaktree Capital Management have reiterated their support for the new venture which aims to pursue their original vision “to restore the unique building to prominence” and “create a world class hotel of international standing”.

In a statement Hoskins Architects wrote: “Following refusal of 2015 applications, the applicants instructed their design team to reassess all aspects of the proposals, focusing primarily on the visual impact of the development. The resulting revised scheme is presented by the applicant as a proposal that takes full cognizance of all concerns regarding the social, cultural, heritage and landscape impact of the development.”

A rival vision by Richard Murphy Architects and Simpson & Brown to turn the Thomas Hamilton designed property into a music school has been approved but cannot proceed until 2022, when an agreement between the City of Edinburgh Council and the hotel developers expires.