WASHINGTON – The Obama administration is amending its regulations for weapons sales to allow the export of armed military drones to friendly nations and allies.

The State Department said Tuesday the new policy would allow foreign governments that meet certain requirements – and pledge not to use the unmanned aircraft illegally – to buy the vehicles that have played a critical but controversial role in combatting terrorism and are increasingly used for other purposes. Recipient countries would be required to sign end-use statements certifying that the drones would not be used for unlawful surveillance or force against domestic populations and would only be used in internationally sanctioned military operations, such as self-defense.

Each sale would be reviewed individually and the pledges would be monitored for compliance, the department said in a statement.

Previously, drone transfers had been governed by regulations that presumed that requests would be denied except in highly unusual circumstances. Certain armed drones – those with a range of 186 miles and able to carry a payload of 1,100 pounds – will still be subject to those restrictions.

The administration said it was making the changes to ensure that military drones are used responsibly and legally. The new policy is also part of a broader U.S. strategy to cooperate with other nations to formulate global standards for the sale, transfer and use of unmanned aerial systems, it said.

The United States has used drones in Pakistan, Afghanistan, Iraq, Yemen and elsewhere to target terrorist leaders. The campaigns are run in parallel by the CIA and the Defense Department, and have been sources of controversy because of claims that innocent people have been killed along with targeted individuals.