WASHINGTON, Jan 20 (Reuters) - Nearly 1,660 Afghans cleared by the U.S. government to resettle in the U.S., including family members of active-duty U.S. military personnel, are having their flights canceled under President Donald Trump's order suspending U.S. refugee programs, a U.S. official and a leading refugee resettlement advocate said on Monday.

The group includes unaccompanied minors awaiting reunification with their families in the U.S. as well as Afghans at risk of Taliban retribution because they fought for the former U.S.-backed Afghan government, said Shawn VanDiver, head of the #AfghanEvac coalition of U.S. veterans and advocacy groups and the U.S. official, who spoke on condition of anonymity.