The top US commander in Afghanistan has been cleared of "inappropriate communications" linked to the Petraeus adultery scandal, officials say. The decision frees him up to lead NATO forces in Europe.
US officials late on Tuesday said that a Pentagon investigation had found concerns over emails sent by John Allen to be "unsubstantiated."
Allen was placed under investigation over alleged "inappropriate" emails sent to the woman whose actions brought former CIA boss David Petraeus' extramarital affair to light.
The general has vehemently denied any wrongdoing, with Barack Obama keeping him in command of approximately 66,000 US forces in Afghanistan, as well as the wider NATO-led International Security Assistance Force.
The 59-year-old's nomination to become the next head of US European Command and NATO's Supreme Allied Commander Europe was put on ice, however. The appointment had been set to be confirmed by the Senate in mid-November.
Path clear to lead way in Europe
The decision to exonerate Allen paves the way for him to assume the European command role after leaving his current posting next month.
Allen became embroiled in the affair in November when the FBI discovered emails sent by Allen to Florida socialite Jill Kelley, who regularly threw parties for senior officers.
The Petraeus scandal first had come to light when Kelley alerted FBI chiefs to anonymous emails that she perceived as threatening. Those messages were traced to Petraeus' biographer Paula Broadwell, who the investigators discovered was having an affair with the then CIA boss, who subsequently resigned.
Investigators said the emails from Allen himself were potentially inappropriate and that he might have transgressed US military rules by committing adultery. Allen has denied having an affair.
Adultery is considered "unacceptable conduct" under US Army rules. It is punishable by dishonorable discharge, forfeiture of pay and allowances, and even a one-year prison term.
Allen succeeded Petraeus at the helm in Afghanistan in July 2011. He himself is to be succeeded in February by General Joseph Dunford.
rc / ccp (AFP, AP, Reuters)