Online retailer Amazon has complained to authorities in Washington that it's taking far too long to get regulatory approval for test flights of its fast-evolving fleet of commercial drones.

Paul Misener, Amazon's vice president for global public policy, told the Senate Subcommittee on Aviation Operations on Tuesday that the company was moving faster on testing its drone technology outside of the United States than it was in its home market.

Amazon is testing drones in the United Kingdom, Israel and other countries. In Germany, Deutsche Post's DHL logistics unit has tested delivery drones.

The Federal Aviation Administration (FAA) says it is dragging on drones because of saftey concerns, and that US airspace is more complex than other countries.

Obsolete before approved

Misener said that though Amazon has recently been allowed to test a delivery drone outdoors in the US, the model approved had become obsolete as the company waited over six months for clearance. The US has a ban on commercial drone flights, but allows a small number of exemptions.

The FAA has now loosened restrictions for companies already allowed the exemption, but that is ulikely to ease concerns that America is falling behind other countries in an important developing technology.

Amazon says the sight of robotic delivery drones will one day be as commonplace as mail trucks and courier vans today. The company says the technology will one day allow it deliver products to customers within 30 minutes of receving an order.

kc /uhe (Reuters, dpa, Amazon)