The Tu-22M designation was used by the Soviet Union during the SALT II arms control negotiations, creating the impression that it was a modification of the Tu-22. Some suggested that the designation was deliberately deceptive, and intended to hide the Tu-22M's performance. Other sources suggest the "deception" was internal to make it easier to get budgets approved. According to some sources, the Backfire-B/C production variants were believed to be designated "Tu-26" by Russia, although this is disputed by many others. The US State and Defense Departments have used the Tu-22M designation for the Backfire.