As if the war in Libya weren’t already complicated and ill-defined enough, NATO Commander Lt. Gen. Charles Bouchard threatened the rebels on Thursday, saying the NATO warplanes would start attacking them too if they kept killing civilians.

NATO spokeswoman Oana Lungescu reiterated this sentiment, saying that NATO “will apply the (UN Security Council) mandate across the board.” It is UN Resolution 1973 that NATO is using as an excuse for its war in Libya.

But it is unlikely to be entirely applied across the board, or NATO’s warplanes will have to start attacking one another. That’s because one top Catholic official in Tripoli said that 40 civilians were killed in his city alone during the bombing campaign.

Though UN Resolution 1973 was initially designed to call for a no-fly zone it also contained language about protecting civilians. This was used by NATO nations as an excuse for the massive air strikes and, at least for some, the notion of funneling arms into the hands of favored rebel factions.