Amazon has come a step closer to launching drone delivery of packages in the US after it received a crucial certificate from the Federal Aviation Administration (FAA).

With the possession of what is called Part 135 air carrier certificate, Amazon can run its fleet of Prime Air delivery drones, CNBC reported on Monday.

According to FAA, Part 135 certification is the "only path for small drones to carry the property of another for compensation beyond visual line of sight".

Following the crucial approval, Amazon said it will start testing customer deliveries, said the report.

"This certification is an important step forward for Prime Air and indicates the FAA's confidence in Amazon's operating and safety procedures for an autonomous drone delivery service that will one day deliver packages to our customers around the world," David Carbon, Vice President of Prime Air, was quoted as saying in a statement.

"We will continue to develop and refine our technology to fully integrate delivery drones into the airspace, and work closely with the FAA and other regulators around the world to realise our vision of 30 minute delivery."

The e-commerce giant started testing delivery drones way back in 2013 with the aim of delivering packages within 30 minutes.

Several other companies, including UPS and Alphabet-owned Wing, have received Part 135 certification from FAA.