The US Federal Aviation Administration (FAA) has allowed the oil company BP to use drones over US territory, the first time the agency has granted permission for commercial drone flights.

BP and drone maker AeroVironment have been given permission to use a Puma drone to survey pipelines, roads and equipment in Alaska, the agency said. The first flight took place on Sunday.

The move to allow a private organisation to conduct drone flights is seen as a loosening of the agency's restrictions on commercial uses of unmanned aircraft, the AP news agency reported.

The Puma is a small, hand-launched craft, which was initially designed for military use.

Last summer, the FAA approved the Puma and another drone, ScanEagle, for flights over the Arctic Ocean to scout icebergs, count whales and monitor drilling platforms.

US Transportation Secretary Anthony Foxx said allowing the use of unmanned aircraft for research was an "important step toward broader commercial use of unmanned aircraft".

Rogue operators

Last week, the FAA said it was considering giving permission to seven filmmaking companies to use drones for aerial photography.

So far, the only exceptions to that ban have been limited flights that have been approved over the Arctic Ocean and now Alaska.

Congress directed the FAA to provide commercial drones access to US skies by September 2015, but the agency's efforts to write safety rules for such flights has been slow, and it is not expected to meet the deadline.

FAA officials are on their third attempt to draft regulations acceptable to the Transportation Department and the White House.

Michael Huerta, FAA administrator, said drafting such rules is complex because they must ensure that the large volume and diversity of manned aircraft in US skies were protected.

Even a small drone that collides with a plane travelling at high speed, or gets chewed up by helicopter rotors, could cause a crash.

Drone industry officials have warned that the longer the FAA takes to write regulations, the more rogue commercial operators will multiply.