Washington - The Obama administration and former intelligence contractor Edward Snowden offered divergent accounts Thursday of his efforts to raise concerns about National Security Agency activity more than a year ago, as each side tried to shape the debate over whether the massive leak of classified information was avoidable.

Intelligence officials released a brief email that Snowden wrote in April 2013 inquiring about legal authorities but raising no concerns about any particular NSA program or law. The suggestion was that the email did not make Snowden a whistleblower. U.S. officials said the NSA had found no other evidence that he had expressed concerns to anyone in a position of authority or oversight.

But in an email to The Washington Post, Snowden, who last year leaked large quantities of classified documents to journalists and who is living in Russia under temporary asylum, called the official release "incomplete."

He said it did not include his correspondence with NSA compliance officials and concerns he had raised about "indefensible collection activities." He repeated claims that he had shown colleagues "direct evidence" of programs that they agreed were unconstitutional.

"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 in response to questions from The Post. "It will not take long to receive an answer."

On Thursday, NSA and White House officials said there were "numerous avenues" that Snowden could have used to raise his concerns. Some U.S. officials asserted, for instance, that he could have gone to Congress but did not. As a contractor, however, he would not have enjoyed whistleblower protection, especially against retaliation.

"The fact is that I did raise such concerns both verbally and in writing, and on multiple, continuing occasions - as I have always said, and as NSA has always denied," Snowden said.

Officials said that to date all they have found is an April 5, 2013, email in which Snowden, who was then working at an NSA facility in Hawaii, asked a legal question arising from a training session that outlined various authorities, from the U.S. Constitution on down.

"I'm not entirely certain, but this does not seem correct, as it seems to imply Executive Orders have the same precedence as law," Snowden wrote in the email, citing a "Hierarchy of Governing Authorities" referenced during the training.

"My understanding is that EOs (executive orders) may be superseded by federal statute, but EOs may not override statute," he wrote in the email released by the Office of the Director of National Intelligence and the NSA. "Am I incorrect in this? Between EOs and laws, which have precedence?"

"Hello Ed," came the reply on April 8, from an NSA lawyer, whose name was redacted. "Executive orders . . . have the 'force and effect of law.' That said, you are correct that E.O.s cannot override a statute."

Snowden's email appears to have presaged his concern about broad surveillance undertaken overseas by the NSA outside of laws regulating domestic collection. Such collection of emails, phone calls and other digital data takes place under executive authority with less stringent privacy protections for U.S. persons.

In a statement, NSA spokeswoman Marci Green Miller said: "The email (from Snowden) did not raise allegations or concerns about wrongdoing or abuse, but posed a legal question that the Office of General Counsel addressed. There was not additional follow-up noted."

The release of the email exchange follows an assertion made by Snowden in a television interview aired Wednesday night that he had brought concerns about the lawfulness of NSA activities to the attention of the agency's Office of the General Counsel.

"I actually did go through channels, and that is documented," he said in the interview with "NBC Nightly News." "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."

Snowden told The Post in December that he raised his concerns face to face with colleagues and supervisors for more than six months. Beginning in October 2012, he said, he brought his concerns about widespread agency surveillance to two superiors in the NSA's Technology Directorate and two in the NSA Threat Operations Center's regional base in Hawaii.

He said he was concerned about the volume of data collected on Americans and showed his colleagues a data query tool that depicts the amounts on color-coded heat maps in real-time.

The NSA did not respond to a query as to whether it had asked Snowden's former co-workers about his accounts of these conversations.

Snowden has said he went to journalists because he felt his efforts to raise concerns internally were being brushed aside. He was raising objections to programs and policies that a federal surveillance court and Congress had secretly approved. Since their disclosure, some of the programs have come under sharp criticism from a presidentially appointed review board and an independent surveillance watchdog agency, as well as leading U.S. technology companies.

Congress is weighing legislation to carry out President Barack Obama's call to end one program - the NSA's mass collection of data about Americans' phone calls.

"Ultimately, whether my disclosures were justified does not depend on whether I raised these concerns previously," Snowden said. "That's because the system is designed to ensure that even the most valid concerns are suppressed and ignored, not acted upon."

On Thursday, Senate Intelligence Committee Chairman Dianne Feinstein, D-Calif., also released the email exchange. The panel last month had asked the NSA for any communications between Snowden and the agency relating to the legality of NSA programs.