* Minister calls for "calm", says German banks more at risk
* French bank shares open lower, underperform sector
* C.Agricole declines to comment; BNP, SocGen unavailable
By Lionel Laurent
PARIS, June 15 France called for calm as top French banks' share price prices fell on Wednesday after rating agency Moody's said it might downgrade them because of exposure to Greece's debt-stricken economy. [ID:nL3E7HF0A4]
"French banks are exposed to Greece...(but) they are less exposed than the German banking sector, for instance. On all these subjects we need to stay calm," Secretary of State for European Affairs Laurent Wauquiez said on French radio.
Wauquiez also reiterated France's opposition to any restructuring of Greek debt that would count as a default.
French banks are among the most exposed to Greek sovereign debt in Europe and hold 9 billion euros ($13 billion) worth, making them vulnerable to a potential restructuring as policymakers thrash out a new rescue plan for Greece.
Moody's cited the impact of a possible Greek default or restructuring as part of the reason it might cut the ratings of France's top three listed banks -- BNP Paribas (BNPP.PA), Credit Agricole (CAGR.PA) and Societe Generale (SOGN.PA).
Asked whether the private sector should participate in a fresh rescue package for Greece, Wauquiez said: "If (Greek debt) restructuring means that the country does not repay its debts, then this is not part of the French government's vocabulary."
Euro zone ministers failed to reach agreement on Tuesday on how private holders of Greek debt should share the costs of a new bailout, putting the onus on the leaders of Germany and France to forge a deal later this week. [ID:nLDE75E060]
BNP shares were down 2.0 percent at 0807 GMT, while Credit Agricole was down 1.4 percent and SocGen was 1.7 percent lower. All three were underperforming the STOXX Europe 600 bank index .SX7P, down 1.1 percent.
Credit Agricole declined to comment on the Moody's report, while BNP and SocGen were not available for comment. The French Banking Federation (FBF) declined to comment. [ID:nL3E7HF0A4]
FBF head Francois Perol, told Reuters on Tuesday banks had not yet been approached on the topic of a private-sector contribution but shared the European Central Bank's concerns over a potential debt restructuring.
ECB officials have consistently ruled out any scheme that is not strictly voluntary, fearing it would be ruled a default by rating agencies and cause a contagion effect to other euro zone high debtor nations. [ID:nLDE75E060] (Additional reporting by Jean-Baptiste Vey; Editing by Dan Lalor) ($1 = 0.6957 euro)