President Obama told the U.N. on Tuesday that he has limited the use of drones, but added several caveats.

"We have limited the use of drones so they target only those who can pose a continuing imminent threat to the United States, where capture is not feasible and there is near-certainty of no civilian casualties," he said.

Obama also told the UN General Assembly that the U.S. is reviewing its policies on surveillance.

"We have begun to review the way that we gather intelligence so as to properly balance the legitimate security concerns of our citizens and allies, with the privacy concerns that all people share," he said.