UPDATE 1-French M6 tv exec says ad revenues up in Sept, Oct

* Too early to say if higher Sept, Oct ad spending will last

* Q3 ad revenues on main M6 channel fell 2.7 pct

(Adds background)

PARIS, Nov 5 (Reuters) - France's second-largest commercial TV broadcaster said on Thursday ad revenues had picked up in September and October but it was too early to say whether this marked the start of a durable recovery.

"The trend really turned around in September after the summer holidays," Jerome Lefebure, finance director of M6 (MMTP.PA), told Reuters in an interview.

The upturn continued into October but there is too little visibility to draw parallels for the rest of the year, he added.

Lefebure was speaking after M6 announced third-quarter ad revenues for its flagship M6 channel fell 2.7 percent.

Group revenues rose 9.2 percent to 296 million euros.

M6 shares closed earlier down 0.4 percent at 17.36 euros.

Both M6 and larger rival TF1 (TFFP.PA), which reports next week, have been hit by deep cuts to advertising budgets by companies and face competition from the Internet.

M6, which owns French football club Les Girondins de Bordeaux, has abstained from making forecasts for 2009.

Executive Chairman Nicolas de Tavernost told investors in July to brace themselves for another year of difficult advertising markets in 2010.

In October, Tavernost said the bleak period for ad sales was over, but saw no cause for euphoria. He said he hoped the fall in advertising sales at M6 would be less marked in the second half of the year than in the first when sales fell 14.1 percent. (Reporting by Cyril Altmeyer, Dominique Vidalon; editing by Simon Jessop)