WASHINGTON -- A U.S. military officer's media briefing about plans for an Iraqi-led ground offensive in Mosul, including its expected timing, amounted to a mistaken disclosure of "military secrets," Defense Secretary Ash Carter said Tuesday.
The briefer, whose presentation for reporters at the Pentagon on Feb. 19 was authorized by U.S. Central Command, said the U.S. wanted the Iraqis to launch the offensive in Mosul in April or May, although he also said it might go later.
"That clearly was neither accurate information nor, had it been accurate, would have been information that should be blurted out to the press," Carter told the Senate Armed Services Committee. "So it's wrong on both scores."
It now appears likely that the offensive will not begin this spring, with Iraq's security forces requiring more time for U.S.-organized training. It has been widely known for months that the offensive is in the planning stages and that it would likely mark a decisive moment in the campaign to dislodge the Islamic State from Iraq.
Islamic State fighters overran Mosul last June. Iraqi government forces folded quickly, leading to the start of a U.S.-led bombing campaign in Iraq in August.
Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, who was testifying alongside Carter, said he had discussed the Mosul briefing with Gen. Lloyd Austin, head of Central Command.
"He's conducting an internal inquiry," Dempsey said, adding that he is confident Austin will "take the appropriate action." He did not say what that might be.
The briefing was done by an officer at Central Command headquarters in Tampa, Florida. He spoke by phone to a group of reporters in the Pentagon on condition of anonymity under ground rules set by Central Command.
The episode is remarkable in at least two respects. It was unusual for the U.S. military to disclose in advance the expected timing of an offensive as well as details about the makeup of the Iraqi force that would undertake it. And it was curious that a secretary of defense would wait nearly two weeks after such a briefing to denounce it publicly for having spilled military secrets.
Asked about it by reporters twice last weekend, Carter was more circumspect.
"The important thing is that it will get done when it can be done successfully," he said last Friday, referring to the Mosul offensive. "And even if I knew exactly when that was going to be, I wouldn't tell you." Asked to comment again the following day, Carter said it's important to keep the public informed, "consistent with security and other considerations."
On Tuesday, he was more pointed and expansive in directly criticizing Central Command.
"It is important that we be open as a department -- not with military secrets and not with war plans, which was the mistake made in this case -- but we do try to keep the country informed of what we're doing," he said. "It's about protecting them. It is a democracy. And so, openness is important but it has to have limits when it comes to security matters, and those limits obviously weren't respected in this case."