Vivendi SA's (VIV.FR) fully-owned mobile phone unit SFR is readying an initial public offering, French daily Les Echos reported Wednesday citing SFR Chairman Stephane Roussel.

The next two years will be "the toughest" because the company will need to invest heavily in the 4G and optical fiber networks, Mr. Roussel said.

Jean-Rene Fourtou, the head of Vivendi, earlier this year said SFR required a new strategy after the unit was weakened by the emergence of low-cost competitors.

Vivendi wasn't immediately available for comment when contacted by Dow Jones.

Newspaper Web site: http://www.lesechos.fr

Write to Gabriele Parussini at gabriele.parussini@dowjones.com

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