State Department spokesman P.J. Crowley resigned on Sunday, after a recent flap with the administration over comments he made criticizing the Defense Department's handling of suspected WikiLeaks source Bradley Manning.
Crowley, who served as National Security Council spokesman under former President Bill Clinton, came under fire last week after describing the treatment of Manning as "ridiculous, counterproductive and stupid" during an academic forum at the Massachusetts Institute of Technology.
"Given the impact of my remarks, for which I take full responsibility, I have submitted my resignation," Crowley said in a statement on Sunday.
"My recent comments regarding the conditions of the pre-trial detention of Private First Class Bradley Manning were intended to highlight the broader, even strategic impact of discreet actions undertaken by national security agencies every day and their impact on our global standing and leadership," the statement said. "The exercise of power in today's challenging times and relentless media environment must be prudent and consistent with our laws and values."
Clinton said on Sunday she had accepted Crowley's resignation "with regret."
"PJ has served our nation with distinction for more than three decades, in uniform and as a civilian. His service to country is motivated by a deep devotion to public policy and public diplomacy, and I wish him the very best," she said in a statement.
Manning's treatment - he has been detained at the U.S. Marine brig in Quantico, Virginia for several months, and is reportedly held in solitary confinement for 23 hours daily despite never having been convicted for a crime - has spurred outrage among some civil rights advocates.
When questioned about Crowley's comments in a press conference on Friday, President Obama said he had been assured by the Pentagon that the 22-year-old U.S. Army Private was being treated "appropriately."
"With respect to Private Manning, you know, I have actually asked the Pentagon whether or not the procedures that have been taken in terms of his confinement are appropriate and are meeting our basic standards," Mr. Obama said. "They assured me that they are. I can't go into details about some of their concerns, but some of this has to do with Private Manning's safety as well."
Michael Hammer, Principal Deputy Assistant Secretary (PDAS), will serve as Acting Assistant Secretary for Public Affairs, according to Clinton's statement.