The Qatari companies will take a 51 per cent stake in the new entity with 49 per cent held by the French.
The new company will focus on multi-utility facilities and services in the areas of water and wastewater treatment and distribution, power transmission and distribution, district cooling, gas supply and solid waste collection and treatment.
It will bid for multi-utility projects in the region, with Barwa and Qatari Diar themselves likely to be major customers for the firm.
It will offer masterplanning, design, financing, construction and operation, and maintenance services.
The companies signed a memorandum of understanding in May.