With the U.S. Federal Aviation Administration refusing to budge on its strict requirement that commercially operated drones must fly within the operator’s line of sight at all times, Amazon.com Inc., has announced plans to start testing flights in the U.K. instead.

Amazon revealed it has started working with the U.K.’s Civil Aviation Authority to carry out further tests for its planned Prime Air delivery service, including test flights beyond the operator’s line of sight in both rural and suburban areas. In addition, it will also evaluate a number of different sensors that drones use to avoid obstacles. Lastly, it will trial test flights involving multiple drones controlled by a single operator.

“The UK is a leader in enabling drone innovation — we’ve been investing in Prime Air research and development here for quite some time,” Paul Misener, Amazon’s Vice President of Global Innovation Policy and Communications, said in a statement. “This announcement strengthens our partnership with the U.K. and brings Amazon closer to our goal of using drones to safely deliver parcels in 30 minutes to customers in the U.K. and elsewhere around the world.”

Amazon said the tests should also help governments to design future regulations governing drone flights.

Amazon has been forced to carry out its drone tests outside the U.S. due to the FAA’s strict rules governing commercial flights. As well as limiting drone flights to the operator’s visual line of site, drones are also prohibited from flying over members of the public, and pilots are restricted from flying more than one at a time. The FAA does waive some of these rules in special cases, but to do so organizations must apply for a special certificate of waiver and demonstrate they can conduct their operations safely.

It’s not clear if or when the FAA will relax its rules, which only came into being earlier this year, but failing to do so would surely harm the U.S.’s chances of becoming a leading innovator in the field. Indeed, Amazon has previously warned that it would be forced to shift its drone delivery initiative overseas if U.S. regulators refuse to cooperate.