Energy Secretary Chris Wright said Sunday that the Trump-ordered nuclear weapons tests will not involve explosions of any kind.

“I think the tests we’re talking about right now are system tests,” Wright said on Fox News’s The Sunday Briefing. “These are not nuclear explosions. These are what we call noncritical explosions. So you’re testing all the other parts of a nuclear weapon to make sure they deliver the appropriate geometry, and they set up the nuclear explosion.”