MILAN (Reuters) - U.S. asset manager Fortress Investment Group (>> Fortress Investment Group LLC) has entered exclusive talks to buy a 1 billion euro (0.73 billion pounds) portfolio of Italian house loans from Barclays (>> Barclays PLC), two sources close to the matter said.

The British bank is selling its Italian retail network, which comprises 90 branches, as well as performing house mortgages in the country.

Barclays owns 18 billion euros in Italian house loans and was initially looking to start with the sale of a 4 billion euro portfolio.

Sources have previously said Barclays is selling the Italian retail unit and the mortgage portfolio to separate buyers in an effort to maximise value, after strong interest from U.S. asset managers and hedge funds for the mortgages.

One of the sources said Mediobanca's (>> Mediobanca Group) retail arm Che Banca and Dutch group ING (>> ING GROEP) had expressed an interest in the branch network.

Mediobanca CEO Alberto Nagel earlier this month told reporters the bank had a plan of "autonomous growth" for Che Banca when asked about a possible bid for Barclays' Italian network.

Fortress, Mediobanca and ING declined to comment.

(Reporting by Massimo Gaia and Pamela Barbaglia, writing by Valentina Za, editing by Stephen Jewkes)