Moody's to downgrade French banks: sources

French banks have fallen sharply over rising concerns that the debt crisis in the eurozone was reaching a logjam that would force Greece into a credit default.

Assurances from Société Générale that its exposure to eurozone debt was miniscule cut no ice with markets as financial stocks across the continent fell on fears of an eventual break up of the eurozone.

According to some reports, rating agency Moody's is likely to downgrade the three biggest French banks over their exposure to Greek debt.

SocGen said it had an exposure to eurozone periphery debt of €4.3 billion which it said was manageable and declining and further it  would free up €4 billion in divestments by 2013.

Meanwhile, according to some analysts, only an shock and awe move from the ECB or a similar authority like the US Fed or the German or French government could now save markets from an economy shaking crash.

Meanwhile Moody's on Saturday said the review it was conducting of the French banks' due to their exposure to Greece's debt-stricken economy would last over three months.