The White House spokesperson John Kirby expressed to reporters aboard the U.S. presidential plane today, Monday, his concern that the United States is worried about reports indicating that Israel is using white phosphorus. Kirby stated that white phosphorus has a "legitimate military use" for lighting and producing smoke to conceal movements. He added, "It is clear that when we provide materials such as white phosphorus to another army, we fully expect them to be used for those legitimate purposes... and in accordance with the laws of armed conflict."