European stocks extended their early losses on Monday after Moody's Investors Service warning on France added to worries about the euro zone debt crisis.

At 0852 GMT (8:52 a.m. British time), the FTSEurofirst 300 <.FTEU3> index of top European shares was down 2.2 percent at 930.37 points.

Ratings agency Moody's said that a recent rise in interest rates on French government debt and weaker economic growth prospects could be negative for France's credit rating.

Elevated borrowing costs persisting for an extended period would amplify the fiscal challenges the French government faces amid a deteriorating growth outlook, with negative credit implications, Senior Credit Officer Alexander Kockerbeck said in Moody's Weekly Credit Outlook dated November 21.

(Reporting by Blaise Robinson)