CAMPAIGNERS have spoken of their "delight" after plans to turn the historic Royal High School into a new home for Scotland’s only independent music school were given the go-ahead.

The proposal will safeguard the future of the A-listed building on Calton Hill in Edinburgh, which has lain derelict for decades, and bring it back into long-term use.

The planning application, submitted by the Royal High School Preservation Trust (RHSPT), will turn the neoclassical masterpiece a state-of-the-art base for St Mary’s Music School and see the creation of three performance spaces and a 300-seat concert hall in the former debating chamber.

RHSPT Chairman William Gray Muir, Chair of the Trust, said the decision was a "wonderful opportunity" to transform the building for the benefit of all residents in Edinburgh.

He said: “We are delighted that our proposals have received unanimous approval, with the City of Edinburgh Council granting us a special, extended seven-year timescale for planning and listed building consent.

“The former Royal High School is pivotal to Edinburgh’s World Heritage Status and our plans are designed to celebrate, conserve and enhance the site for the people of Edinburgh.

"By making it home to St Mary’s Music School we also hope to reinforce musical education at the heart of the city’s cultural heritage.

“This is a wonderful opportunity to transform a building at risk into a dynamic asset for students, residents, visitors to the city, educational and cultural organisations and the creative sector as a whole."

The plan to turn the building into a hotel had proven controversial amid warnings it could threaten Edinburgh's World Heritage status.

Mr Muir said that the RHSPT proposal meant that this danger had now receded.

He added: “Our plans are fully funded, they bring together world-class culture and heritage in a highly visible and meaningful way and have overwhelming support from local residents and heritage organisations concerned about preserving our UNESCO World Heritage Status. All of this can be achieved without any adverse change to the setting of the historic site.”

The plan to create a new home for the music school attracted a number of high-profile backers, including the comedian Alexander Armstrong, a former pupil.

Other supporters of the plan include Richard Hillier, the headmaster of the Yehudi Menuhin music school, and Professor Jeffrey Sharkey, principal of the Royal Conservatoire of Scotland.

Dr Kenneth Taylor, Headteacher at St Mary’s Music School,said: “Everyone associated with the school and our supporters within the wider musical and cultural community will be hugely excited by today’s good news.

"A move to the Royal High School under the Trust’s plans would enable St Mary’s Music School to have the performance space we have always aspired to. It will enable us to bring music lovers into the school and greatly expand our outreach activities.

“We look forward to a wonderful and unique opportunity to raise our profile on the international stage, drawing attention to the world class standard of education at St Mary's Music School, with music at the heart of everything we do.”

The green flag for the development comes after Edinburgh City Councillors rejected plans for the high school to be turned into a £75 million luxury hotel.

Duddingston House Properties, the developer behind the hotel plan, is currently appealing the decision.

The firm previously won a commercial bid with the council to develop on the site, which technically means that they have until 2022 to submit any new planning application.

A spokesman for Edinburgh Council said there was a contract in place and that it would be inappropriate to comment further.