Ryan Crocker, the U.S. ambassador to Afghanistan, "is expected to step down soon from his post," sources familiar with the matter tell Reuters and a few other news outlets.
CNN adds that while Crocker, a veteran diplomat who reopened the embassy in Kabul in January 2002 and later served as ambassador to Iraq during President George W. Bush's administration, has been ambassador in Afghanistan for just 10 months:
"The relatively short length of his service in the Afghan capital is no surprise. In recent history, American ambassadors have served similar terms."
Last week, The Washington Post reported that "Marine Corps Gen. John Allen, the top commander in Afghanistan, is expected to leave his post early next year and take over the U.S. European Command."
The personnel shifts come, of course, as the U.S. and its NATO allies prepare to hand over responsibility for security to Afghan forces and to withdraw their combat troops from that nation by some time in 2014.