Updated 6 a.m. ET
PERTH, Australia Defense Secretary Leon Panetta cautioned Wednesday against reaching early conclusions about the veracity of allegations against the top U.S. commander in Afghanistan, Gen. John Allen, who is under investigation for what Pentagon officials have said may be "inappropriate" correspondence with a Florida woman linked to the David Petraeus sex scandal.
At a news conference in Australia's Indian Ocean coastal city of Perth, Panetta sought to tamp down a wave of speculation about the nature of Allen's actions, which have added a new dimension to the Petraeus matter.
"No one should leap to any conclusions here," Panetta said in his first public comments on the matter when a reporter asked what Allen might have done wrong. Panetta declined to characterize Allen's actions in any way.
Panetta said he supports Allen, who has been in command in Kabul since July 2011. He took over that summer for Petraeus, who retired from the Army to head the CIA.
"He certainly has my continued confidence to lead our forces and to continue the fight," Panetta said.
The head of NATO also expressed faith in Allen on Wednesday. NATO Secretary General Anders Fogh Rasmussen told reporters at NATO headquarters in Brussels that he has "full confidence" in Allen.
The Pentagon chief declined to explain the nature of Allen's correspondence with Jill Kelley, the Florida socialite connected to the scandal that led to Petraeus' resignation last week as director of the CIA.
One defense official told CBS News the communications were "flirtatious."
Secretary of State Hillary Rodham Clinton, who appeared with Panetta and their Australian counterparts at Wednesday's news conference, declined to comment on the Allen case except to suggest it has not harmed the war effort.
She said U.S. officials have discussed the matter with allied officials.
"There has been a lot of conversation, as you might expect, but no concern whatsoever being expressed to us because the mission has been set forth and it's being carried out," Clinton said.
Panetta announced Tuesday while flying to Australia that he had ordered the Defense Department's inspector general to investigate Allen based on material referred to the Pentagon on Sunday by the FBI.
Allen told Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, that he is innocent of misconduct, according to Col. David Lapan, Dempsey's spokesman.
Lapan said Wednesday that Dempsey called Allen on Tuesday from Perth, where Dempsey attended meetings with Panetta. Dempsey has not commented publicly.
Panetta also announced Tuesday that the Obama administration put on hold Allen's nomination to be the next commander of U.S. European Command and the top NATO general. Allen's Senate confirmation hearing was to have been held Thursday.
Panetta said in Perth that putting a hold on the nomination was the "prudent" thing to do.
Allen, who was in Washington when Panetta announced the investigation and has not yet returned to his headquarters in Kabul, has not publicly commented on the matter.
One senior official told CBS News correspondent David Martin that the vast majority of the emails between Allen and Tampa socialite Jill Kelley "are completely innocuous," and he thinks many of them are duplicates. He said that in some of the emails Kelley would say, "Saw you on television and you were terrific," and Allen would write back with, "Thanks, sweetheart." The official also added that the two never discussed sex and that Allen had never been alone with Kelley.