Italian energy group Enel is expected to take a 12.5 percent stake in a project to build a second EPR nuclear reactor in France, with a deal likely to be signed on Tuesday, sources close to the matter said.

Energy company EDF of France and Enel reached an agreement in November 2007 that enabled Enel to participate in French plans to build third-generation European Pressurised Reactors (EPR).

Enel was given the right to a 12.5 percent interest in an EPR being built in Flamanville, northwestern France, as well as to a similar-sized stake in five other future EDF reactors.

The second EPR is to be located in Penly, northern France.

A diplomatic source said that "an accord should be announced on Enel's participation in the second (French) EPR" at a Franco-Italian summit in Rome on Tuesday.

An Italian source also said the deal was expected to be signed on Tuesday.

The French presidency would neither confirm nor deny the report but said it was possible that "something could be signed" during the summit, as talks between EDF and Enel had gone "very well."

Enel declined to comment.