LandSecs this morning announced its had bought the former home of investment bank Lazard at 21 Moorfields for £16.5m.
The site, comprising vacated 1970s offices and the Crossrail worksite, is located at the western entrance to Liverpool Street Crossrail station.
The developer said it had now submitted plans for two office buildings of 410,000 sq ft and 100,000 sq ft around a large landscaped public plaza.
Under the deal, LandSecs will own the site on two separate 250-year leases at ground rents of 5% of the net rents received.
At the point of committing to construction, Transport for London will have the option of participating in the development with a financial interest of 15-25%. If TfL takes up the option it will share all costs.
Work on the site is set to start in 2018 when construction of the Crossrail station is complete.