MADRID, July 28 (Reuters) - Buyout fund Cinven has bought a majority stake Restaurant Brands International’s unit in the Iberian peninsula in a deal valued at 1 billion euros ($1.18 billion), the companies said in a joint statement on Wednesday. The founders of Restaurant Brands Iberia and Burger King Europe GmbH - the European branch of the fast-food chain - will retain a minority stake in the Iberian unit, and the current executive team will stay in place, the statement added. ($1 = 0.8464 euros) (Reporting by Clara-Laeila Laudette; editing by Inti Landauro) Our Standards: The Thomson Reuters Trust Principles.