Snowden was responding to critics who said he should have discussed his concerns within the agency, before leaking documents to the press.
"I actually did go through channels, and that is documented," he said. "The NSA has records, they have copies of emails right now to their Office of General Counsel, to their oversight and compliance folks, from me raising concerns about the NSA's interpretations of its legal authorities. ... The response more or less, in bureaucratic language, was, 'You should stop asking questions.'"
But the NSA said in a statement Thursday that it had only recovered only "one e-mail inquiry" from the former contractor "asking for an explanation of some material that was in a training course he had just completed."
"The e-mail did not raise allegations or concerns about wrongdoing or abuse, but posed a legal question that the Office of General Counsel addressed," the agency said. "There are numerous avenues that Mr. Snowden could have used to raise other concerns or whistleblower allegations. We have searched for additional indications of outreach from him in those areas and to date have not discovered any engagements related to his claims."
In the April 5, 2013 email, Snowden asks whether "Executive Orders have the same precedence as law" in apparent relation to "mandatory USSID 18 training."
Someone from the Office of General Counsel responded to the email, writing that "Executive Orders have the 'force and effect of law,'" but "cannot override a statute."
In an email to the Washington Post, Snowden accused the NSA of issuing an "incomplete" release of his communications.
"If the White House is interested in the whole truth, rather than the NSA's clearly tailored and incomplete leak today for a political advantage, it will require the NSA to ask my former colleagues, management, and the senior leadership team about whether I, at any time, raised concerns about the NSA's improper and at times unconstitutional surveillance activities," Snowden said. "It will not take long to receive an answer."