International Power has rejected a 6 billion pound approach by French utility GDF Suez to buy the 30 percent of the British electricity producer it does not already own.

The members of the Independent Committee have unanimously concluded that the indicative proposal of 390 pence per share undervalues IPR, the company said in a statement on Wednesday. Accordingly GDFS has been notified that the Independent Committee is unable to accept the indicative proposal.

International Power's independent non-executive directors also noted in a brief, three-paragraph statement that GDF is generally restricted from making a takeover offer for it before August 3, 2012, unless it has their backing.

GDF's preliminary approach announced last week valued International Power at 19.9 billion pounds but at 390 pence a share was only slightly above where the stock had already been trading.

(Corrects final paragraph to make clear valuation refers to International Power, not GDF)

(Reporting by Paul Hoskins; Editing by Clara Ferreira-Marques)