LOS ANGELES, Feb. 21 (Xinhua) -- United Parcel Service Inc. (UPS) announced on Tuesday that it successfully tested residential drone delivery in Lithia, Florida on Monday.

The drone launched from the top of a UPS package car, autonomously delivered a package to a home and then returned to the vehicle while the delivery driver continued along the route to make a separate delivery, according to the company's statement.

"This test is different than anything we've done with drones so far. It has implications for future deliveries, especially in rural locations where our package cars often have to travel miles to make a single delivery," said Mark Wallace, UPS senior vice president of global engineering and sustainability.

Rural delivery routes are the most expensive to serve due to the time and vehicle expenses required to complete each delivery, according to the company.

In the test, the drone made one delivery while the driver continued down the road to make another, making it a possible role in package delivery for drones in the future.

A reduction of just one mile per driver per day over one year can save UPS up to 50 million U.S. dollars. UPS has about 66,000 delivery drivers on the road each day, the company said.

Drone delivery has been fashionable among top world e-commerce and express companies, with Amazon, Google, Chinese express company Shunfeng Express and Chinese e-commerce giant JD.com having successfully tested their own drone delivery service.

Despite the successful tests, drone delivery still has an uncertain future as civil aviation regulations may get in its way.

U.S. Federal Aviation Administration (FAA) requirements effectively ban drone deliveries by requiring operators to retain a line of sight, avoid flying drones over people, and stick to a low weight limit, according to a report by Wall Street Journal.

Proposed FAA guidelines for operation over crowds were supposed to be released by the end of 2016 but were delayed due to security concerns, according to a Bloomberg report.

In China, things are not much different as the Civil Aviation Administration of China requires a license or administration by an association, which are not yet in place, for any unmanned aerial vehicle with weight above seven kilograms or flying out of the pilot's sight.