"I have a lot of confidence generally in the FBI," Obama said, offering only qualified words of support for the agency. But the president added that if the FBI had given the White House an earlier heads-up about the inquiry into possible national security violations, he might now be facing questions about why he'd interfered in a criminal investigation.
The inquiry that led to CIA Director David Petraeus' resignation began last summer, but the White House didn't learn about it until the day after the election. Two days later, on Friday, Petraeus resigned after acknowledging he'd had an affair with his biographer, Paula Broadwell.
As Obama spoke about the scandal from the White House, legislators on Capitol Hill were grilling FBI and CIA officials about the same issues: whether national security was jeopardized and why they didn't know about the investigation sooner.
FBI Director Robert Mueller and deputy FBI Director Sean Joyce met first with Senate Intelligence Committee Chairwoman Dianne Feinstein, D-Calif., and ranking Republican Saxby Chambliss of Georgia, then crossed the Capitol to meet with the House Intelligence Committee.
Acting CIA Director Michael Morell went before the House panel next, after meeting Tuesday with top Senate intelligence officials to explain the CIA's take on events that led to Petraeus' resignation.
Lawmakers are especially concerned over reports that Broadwell had classified information on her laptop, though FBI investigators say they concluded there was no security breach.
Obama, for his part, said he had "no evidence at this point from what I've seen that classified information was disclosed that in any way would have had a negative impact on our national security."
US officials say Broadwell sent harassing, anonymous emails to a woman she apparently saw as a rival for Petraeus' affections. That woman, Jill Kelley, in turn traded sometimes flirtatious messages with Afghan war chief General John Allen, possible evidence of another inappropriate relationship.
Officials who have seen the communications between Allen and Kelley describe some of their emails as overly flirtatious and "suggestive," and say their release would be embarrassing for the general.
Word surfaced on Wednesday that Kelley's pass to enter MacDill Air Force Base has been indefinitely suspended, a decision made at the base. Pentagon spokesman Lieutenant Colonel Steven Warren said she can still enter the base but now must report to the visitor center and sign in like anyone else who doesn't have a pass.
Kelley's complaints about threatening emails triggered the FBI investigation that led to the resignation of Petraeus and a probe into communications between her and Allen, the top US commander in Afghanistan.
Senate Intelligence Committee Chairwoman Dianne Feinstein was asked by reporters if there was a national security breach with the Petraeus affair and said she had "no evidence that there was at this time."
Feinstein said on Wednesday that Petraeus would testify before Congress - but not about the affair. She said he had agreed to appear to talk about the Libya attack on September 11 that killed the U.S. ambassador and three other Americans, but said no date had been set.
The Senate Armed Services Committee planned to go ahead with Thursday's scheduled confirmation hearing on the nomination of Marine Corps General Joseph Dunford, who is to replace Allen as commander of US and NATO forces in Afghanistan, if Allen is indeed promoted.
Obama had hoped to use the afternoon news conference, his first since his re-election, to build support for his economic proposals heading into negotiations with lawmakers on the so-called fiscal cliff. But his economic agenda had to share time with questions about the widening sex scandal.
Allen has been allowed to stay in his job as commander of the Afghan war and provide a leading voice in White House discussions on how many troops will remain in Afghanistan - and for what purposes - after the US-led combat operation ends in 2014. The White House said the investigation would not delay Allen's recommendation to Obama on the next phase of the US troop drawdown from Afghanistan, nor would it delay the president's decision on the matter. Allen's recommendation is expected before the end of the year.
But Obama did put on hold Allen's nomination to become the next commander of US European Command as well as the NATO supreme allied commander in Europe, at the request of Defense Secretary Leon Panetta, until Pentagon investigators are able to sift through the 20,000-plus pages of documents and emails that involve Allen and Kelley.
NATO Secretary-General Anders Fogh Rasmussen said Wednesday that he had "full confidence" in Allen and looked forward to working with him if he is ultimately confirmed.
The FBI decided to turn over the Allen information to the military once the bureau recognized it contained no evidence of a federal crime, according to a federal law enforcement official who was not authorized to discuss the matter on the record and demanded anonymity. Adultery, however, is a crime under the Uniform Code of Military Justice.
Allen, 58, worked to save his imperiled career. He told Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, that he is innocent of misconduct, according to Colonel David Lapan, Dempsey's spokesman.
At a news conference Wednesday in Perth, Australia, Panetta said, "No one should leap to any conclusions," and said he is fully confident in Allen's ability to continue to lead in Afghanistan. He added that putting a hold on Allen's European Command nomination was the "prudent" thing to do.
Known as a close friend of Petraeus, Kelley, 37, triggered the FBI investigation that led to the retired four-star general's downfall as CIA director when she complained about getting anonymous, harassing emails. They turned out to have been written by Broadwell, who apparently was jealous of the attention the general paid to Kelley.