The proposed plan represents a major step by U.S. intelligence agencies to spot and track down terrorist networks and crime syndicates by bringing together financial databanks, criminal records and military intelligence. The plan, which legal experts say is permissible under U.S. law, is nonetheless likely to trigger intense criticism from privacy advocates.

Financial institutions that operate in the United States are required by law to file reports of "suspicious customer activity," such as large money transfers or unusually structured bank accounts, to Treasury's Financial Crimes Enforcement Network (FinCEN).

The Federal Bureau of Investigation already has full access to the database. However, intelligence agencies, such as the Central Intelligence Agency and the National Security Agency, currently have to make case-by-case requests for information to FinCEN.