AFRICOM commander Gen. Carter Ham on the — frankly impossible to follow — rules of engagement in Libya:

“We do not provide close air support for the opposition forces. We protect civilians,” Gen. Carter Ham, the top military official in charge of the operation, told reporters in a conference call on Monday. The problem is, there is no official communication with the rebel forces on the ground and there is no good way to distinguish the rebel fighters engaged against the government forces from civilians fighting to protect themselves, he said.
“Many in the opposition truly are civilians…trying to protect their civilian business, lives, and families,” said Ham. “There are also those in the opposition that have armored vehicles and heavy weapons. Those parts of the opposition are no longer covered under that ‘protect civilians’ clause” of the U.N. Security Council resolution that authorized military intervention.
“It’s a very problematic situation,” Ham admitted. “Sometimes these are situations that brief better at the headquarters than in the cockpit of an aircraft.”
So how are pilots in the air supposed to tell the difference? If the opposition groups seem to be organized and fighting, the airplanes imposing the no-fly zone are instructed not to help them.
“Where they see a clear situation where civilians are threatened, they have… intervened,” said Ham. “When it’s unclear that it’s civilians that are being attacked, the air crews are instructed to be very cautious.”
“We have no authority and no mission to support the opposition forces in what they might do,” he added.

Josh Rogin has more at Foreign Policy.