Britain’s biggest contractor said it would use the £150m cash raised from the deal to reduce borrowings and develop its global infrastructure business.

Andrew McNaughton, CEO of Balfour Beatty, said: “The sale of the UK FM business represents an important step in our evolution as we intensify our focus on infrastructure.

“In addition to finding a good new home for the business, its customers and employees, this transaction has achieved good value and will enable us to allocate more resource to target growth sectors and markets in the future.”

The business is expected to continue to provide facilities management services to Balfour Beatty’s current portfolio of social infrastructure PPP assets and to collaborate with Balfour on the development of its investments in the future.

Its clients include nine major hospitals, 200 schools, 500 government buildings and eight nuclear power stations.

The 9,000 strong staff business boasts several major contracts with clients including the Department for Work and Pensions, HM Revenue & Customs and North East Lincolnshire Council as well as the Romec joint venture with the Royal Mail Group.

GDF Suez chief executive Gerard Mestrallet said: “This transaction allows us to more than double our energy efficiency operations in Britain.”

Balfour Beatty WorkPlace made a £21m operating profit last year from £482m of revenue and employs 9,000 staff. Gross assets at 31 December 2012 were £197m.