PARIS (Reuters) - General Electric <GE.N> plans to submit a bid as early as Thursday to acquire French wind power group Adwen, jointly owned by Spain's Gamesa <GAM.MC> and France's Areva <AREVA.PA>, weekly magazine La Lettre de l'Expansion reported on Monday.

Sources told Reuters in July that General Electric and German wind turbine maker Senvion <SENG.DE> were preparing bids for Adwen.

The paper said GE was preparing to submit its bid on Aug. 24, but did not give any further details. General Electric declined to comment, while Areva was not immediately available to comment.

Germany's Siemens <SIEGn.DE> has agreed to take over Gamesa's 50 percent stake in Adwen as part of its 1 billion euro ($1.1 billion) deal to buy a majority stake in Gamesa. It has also made an offer for Areva's Adwen stake.

However, under the terms of a side-deal agreed in connection with Siemens's buyout of Gamesa, Areva has until mid-September to look for an alternative buyer.

(Reporting by Dominique Rodriguez; Writing Bate Felix; editing by John Irish)