British bank regulators on Friday fined James E. Staley, the chief executive of Barclays, over his attempt to unmask a whistle-blower within the bank.

The bank, however, said it would continue to stand by its top executive, who has been tasked with bringing stability to the three-centuries-old institution after years of management turmoil.

Barclays said that two British regulators, the Financial Conduct Authority and the Bank of England’s Prudential Regulation Authority, had fined Mr. Staley, though it did not disclose the amount. The regulators also required Barclays to submit reports on parts of its whistle-blowing program, the bank said, though it added that the regulators did not take any action against Barclays itself.

But Barclays said the regulators did not demand that he resign, nor that he acted with a lack of integrity or was not fit to remain the bank’s chief executive.