European banks, including Spain's Grupo Santander and France's BNP Paribas, said Sunday their clients and shareholders face billions of euros of losses on investments with Bernard Madoff, underscoring the global reach of the alleged Ponzi scheme run by the veteran New York money manager.

Santander, the eurozone's largest bank by market value, said its clients had an exposure of €2.33bn ($3.1bn) to Madoff's investment funds, mainly through its Optimal Strategic US Equity fund.