The scheme will see a mix of offices, hotel and retail space delivered in the city centre, according to the BBC.
It is understood work will begin "within weeks".
The four-acre site is located adjacent to Haymarket Station and is to be developed by Interserve and Tiger Developments, while Network Rail has agreed to let preparatory works to begin on the railway tunnels on the site next month.
-- Advertisement --
On-site construction is set to start in spring 2014, with the first buildings' phase due to be completed in 2016.
Worth a total £150m, the development has full planning consent for 404,000 sq ft of office accommodation and 60,000 sq ft of commercial and leisure space, together with a 165-bedroom hotel and a 320-space underground car park.
David Westwater, Interserve's development director, is quoted as saying: "This agreement with Network Rail to start work on the site represents a significant milestone for one of Edinburgh's last remaining gap sites.
"We are looking forward to completing the underground works during 2014, allowing for above-ground construction to start in early 2015."
Simon Fox, Tiger development director, added: "The proposals for a mix of leisure, retail and office space linked by open public spaces will act as a catalyst to regenerate the commercial heart of the area as well as create jobs."
(JP/CD)
