"Under an agreement between the partners, Yum! Brands has decided to use its right to buy Rostik's-KFC business, a 100 percent of which belongs to Rostik Group," the source told RIA Novosti.

In 2005, Rostik Group and Yum! Brands struck a strategic alliance agreement to manage and develop fast food restaurants under the Rostik's-KFC brand which specialises on chicken dishes, in Russia and the CIS.

Russia's Federal Antimonopoly Service said on its site that it had approved a Yum! Brands Restraurants International Managment request to buy Rostik's-KFC's managing company.

"It is expected that the change in Rostik's-KFC ownership may be finalised in June-July 2010," the source said.

Rostik's-KFC belongs to its founder Rostislav Ordovsky-Tanayevsky Blanco. Rostik's-KFC's network has about 160 restaurants, most of which work on a franchise basis.