President Donald Trump has suggested multiple times to senior Homeland Security and national security officials that they explore using nuclear bombs to stop hurricanes from hitting the United States, according to sources who have heard the president’s private remarks and been briefed on a National Security Council memorandum that recorded those comments, Axios reported.

During one hurricane briefing at the White House, Trump said, “I got it. I got it. Why don’t we nuke them?” according to one source who was there. “They start forming off the coast of Africa, as they’re moving across the Atlantic, we drop a bomb inside the eye of the hurricane and it disrupts it. Why can’t we do that?” the source added, paraphrasing the president’s remarks.

The briefer “was knocked back on his heels,” the source in the room added.

Trump also raised the idea in another conversation with a senior administration official, Axios added. A 2017 NSC memo describes that second conversation, in which Trump asked whether the administration should bomb hurricanes to stop them from hitting the homeland. A source briefed on the NSC memo said it does not contain the word “nuclear”; it just says the president talked about bombing hurricanes.

A different senior administration official, who has been briefed on the president’s hurricane bombing suggestion, defended Trump’s idea and said it was no cause for alarm. “His goal—to keep a catastrophic hurricane from hitting the mainland—is not bad,” the official said. “His objective is not bad.”

The Axios sources said that Trump’s “bomb the hurricanes” idea never entered a formal policy process.

A senior administration official said, “We don't comment on private discussions that the president may or may not have had with his national security team.”

The notion that detonating a nuclear bomb over the eye of a hurricane could be used to counteract convection currents dates to the former US President Dwight Eisenhower era, when it was floated by a government scientist.