The three-year account will see Interserve provide daily cleaning, window cleaning and periodic cleaning services to all of SSE and SGN’s 70 corporate offices located across the UK.

The facilities management group already provides asbestos removal services to around 90 industrial sites for both companies.

Under the contract, Interserve said it would roll out new management and timekeeping systems that will “deliver significant efficiencies and synergies” for both SSE and SGN. The firm will also transfer around 200 people to their team under the terms of the contract.

Jeff Flanagan, managing director of commercial at Interserve, said: “We look forward to starting a new partnership with SSE and SGN. Our experience of delivering consistent, cost-effective cleaning services for customers with large and diverse corporate estates makes us the perfect choice for this account, and we look forward to building on this relationship in the years to come.”