US energy secretary says no 'mushroom cloud' expected from Trump's nuclear tests

US Energy Secretary Chris Wright said on Sunday that there will be no "mushroom cloud" from President Donald Trump's order to resume nuclear weapons testing, clarifying that the planned activities involve system checks.

"I think the tests we're talking about right now are system tests... These are not nuclear explosions. These are what we call noncritical explosions," Wright told Fox News, explaining Trump's announcement last week instructing the Pentagon to "immediately" begin nuclear tests.

He said such tests involve checking "all the other parts of a nuclear weapon to make sure they deliver the appropriate geometry and they set up the nuclear explosion."

"This is not something where people who live in the Nevada desert should expect to see a mushroom cloud at some point," said Wright.

Trump's order came after 33 years without US nuclear weapons testing and follows testing programs by other countries.

Earlier on Friday, Russian Security Council chief Sergey Shoygu said Russia would conduct nuclear tests if other countries do so. The Kremlin noted that Russia tested a new nuclear-powered cruise missile and autonomous torpedo this month, but has not tested an actual nuclear weapon.