The sale of the business in Romania is part of Enel's strategy to reduce net debt to 51-52 billion euros ($55 billion to $56 billion) at the end of this year from a peak of nearly 70 billion euros reached at the end of September.

"We have a process that is not finished, but it's going in the right direction, and we have selected a preferred bidder (for Romania assets)," Enel's Chief Executive Francesco Starace told Reuters on the sidelines of an energy conference.

"This is a question of letting this process be completed... I think (it will happen) before the end of June," he added.

Enel said last year it entered exclusive talks with Greece's PPC about its business in Romania, which analysts have said could have a value of more than 1 billion euros.

Italy's biggest utility announced an ambitious asset sale plan in November to cut its debt pile and focus on six main markets in Europe and the Americas.

It has also started a process of selling assets in Argentina and in Peru.

In Argentina, Enel was "close" to selecting a preferred bidder for its generation assets, Starace added, without elaborating.

In Latin America Enel was also in talks with renewable energy developers, to sell some of its Chilean solar power assets, sources familiar with the matter told Reuters last year.

After completing its asset sale Enel plans to focus on its core markets of Italy, Spain, the United States, Brazil, Chile and Colombia.

($1 = 0.9314 euros)

(Reporting by Nerijus Adomaitis, additional reporting by Francesca Landini in Milan; Editing by Emelia Sithole-Matarise)