A New York Times reporter is calling the Obama administration "the greatest enemy of press freedom that we have encountered in at least a generation."

James Risen, who is battling the administration over an order that he testify in the trial of an accused leaker, made the remarks Friday at the Sources and Secrets conference in New York City.

Poynter reported that Risen accused the administration of pushing to "narrow the field of national security reporting" and threatening to punish any who go beyond those supposed limits. Risen criticized the administration for its aggressive prosecution of leaks and said the media has been "too timid" on the issue, Poynter reported.

The administration has faced criticism from press and transparency groups for cracking down on leakers and whistle-blowers, and for monitoring journalists -- including journalists with The Associated Press and Fox News.

The Justice Department, under public and presidential pressure, proposed reforms but members of Congress are also pushing for a federal media shield bill to protect journalists from having to reveal confidential sources.