The prospect of large penalties for allegedly violating US sanctions has sparked a debate within BNP Paribas' executive suites over whether top officials, including the French bank's chairman, Baudouin Prot, should resign, according to people familiar with the matter.

A longtime rift between BNP Paribas's traditionally cautious retail division and its more aggressive investment bankers has deepened in recent weeks as it emerged that US authorities were pushing BNP Paribas to pay more than $10 billion and plead guilty to criminal charges to resolve investigations into the bank, the people said.