The European Central Bank said on Monday it was in touch with Bloomberg LP after the financial data and news company had allowed journalists to see some information about terminal usage.

Bloomberg customers, including the U.S. Federal Reserve and the U.S. Treasury, are examining whether there could have been leaks of confidential information.

"The ECB takes the protection of confidentiality in the usage of data products by ECB management and staff very seriously," an ECB spokesman said. "Our experts are in close contact with Bloomberg."

The financial data and news company said on Friday it had restricted reporters' access to client data last month after a client complained.

Bloomberg, whose terminals are widely used in the global financial industry, had allowed journalists to see some information about terminal usage, including when customers had last logged in, and how often they used messaging or looked up data on broad categories, such as equities or bonds.