That's down from about 23,000 U.S. troops there now.
But Ambassador Ronald Neumann says the United States will remain involved in the south in a variety of combat support roles.
The comment came one day after ISAF commander General David Richards said NATO will be sending as many as 6,000 troops to southern Afghanistan -- twice the current number -- as the alliance prepares to expand its mission there.
The NATO-led ISAF also plans to expand into eastern Afghanistan later this year.
RFE/RL Afghanistan Report
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