Italian teams Aironi and Praetorians Roma have been handed the chance to compete against the best teams of Wales, Ireland and Scotland and join the Magners League from 2010-11.
The two franchises were chosen from a group of four and now have until September 30 to provide financial guarantees to show they can support a team in the Celtic league.
Bennetton Treviso and Duchi Nord-Ovest also submitted proposals to the Italian Rugby Federation (FIR) to attempt to win the right to represent their country, but Aironi, from Viadana, and capital team Praetorians were given the green light to go head-to-head with the likes of last year's champions, Munster.
The FIR has instigated a financial scheme to help the two franchises to sign Italian players, in an attempt to get as many native players competing at the highest level of club competition.
Praetorians will be based in Rome and will play at the city's Stadio Flaminio, while Aironi will be based in Viadana but will play some matches in the city of Reggio Emilia.
England's preparations for the Autumn International series were potentially dealt a further blow as Maro Itoje was forced to undergo an x-ray after Saracens' European victory over Scarlets on Saturday night.