UPDATE 2-EDF ups stake in Austria's Estag to 25 pct

* EDF increases Estag stake

* Move follows press reports it would sell it to Verbund

* Spokeswoman says EDF has no intention of selling stake (Adds comment from EDF spokeswoman)

PARIS, June 26 (Reuters) - French utility EDF (EDF.PA) said on Friday it had increased its stake in Austrian energy supplier Estag to 25 percent from 20 percent by buying GDF Suez's (GSZ.PA) 20 percent stake in a holding company.

EDF said it is now the sole shareholder in Societe d'Investissement en Autriche (SIA), which owns 25 percent of Estag.

A spokeswoman for EDF told Reuters the group had "no intention of selling on the stake at this stage."

Austrian newspaper Der Standard reported on Thursday that EDF was planning to sell its stake in Estag to Verbund (VERB.VI), Austria's largest utility.

Der Standard said EDF would first buy out GDF Suez and then offer the stake to Verbund, without saying where it got the information.

Land of Styria owns the remaining 75 percent of Estag, which operates in the energy and waste management sectors and has around 40 subsidiaries in Austria. (Reporting by Helen Massy-Beresford; editing by John Stonestreet and Gerald E. McCormick)