President Barack Obama's administration took the first step to opening the skies above the U.S. to widespread civilian drone flights while proposing strict limits on commercial operations and privacy rules for those flown by government agencies.

The Federal Aviation Administration on Sunday unveiled a proposal to permit businesses to use small unmanned aircraft, so long as they are flown at low altitudes by a person who is at least 17 years old, passes a knowledge test and gets an FAA certificate. Flights wouldn't be allowed out of sight of the operator or over crowds, and couldn't exceed 100 mph (161 kph), according to a fact sheet issued by the agency.

"Technology is advancing at an unprecedented pace and this milestone allows federal regulations and the use of our national airspace to evolve to safely accommodate innovation," Transportation Secretary Anthony Foxx said in a statement.