Solutions will become known as Solutions-Digitas. The new entity will service Solutions' existing clients as well as offering an Indian service for Publicis Groupe global clients.
Digitas was acquired by Publicis Groupe last year and has since expanded into the UK, Greater China, Japan and France.
Solutions, which joined the Publicis stable in 2005, specialises in direct, digital and promotions marketing.
Alan Rutherford, the Digitas global chief executive, said: "This illustrates our commitment to establishing a cutting-edge international network."