The US is not planning to conduct nuclear explosions, Energy Secretary Chris Wright has said, calming global concerns after President Donald Trump called on the military to resume weapons testing.

These are not nuclear explosions, Wright told Fox News on Sunday. These are what we call non-critical explosions.

The comments come days after Trump wrote on Truth Social that he had directed defence officials to start testing our nuclear weapons on an equal basis with rival powers.

But Wright, whose agency oversees testing, said people living in the Nevada desert should have no worries about seeing a mushroom cloud.

Americans near historic test sites such as the Nevada National Security Site have no cause for concern, Wright said. 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.

Trump's comments on Truth Social last week were interpreted by many as a sign the US was preparing to restart full-scale nuclear blasts for the first time since 1992.

In an interview with 60 Minutes on CBS, which was recorded on Friday and aired on Sunday, Trump reiterated his position.

I'm saying that we're going to test nuclear weapons like other countries do, yes, Trump said when asked by CBS's Norah O'Donnell if he planned for the US to detonate a nuclear weapon for the first time in more than 30 years.

Russia's testing, and China's testing, but they don't talk about it, he added.

Pressed further on the topic, Trump said: They don't go and tell you about it.

As a "responsible nuclear-weapons state, China has always... upheld a self-defence nuclear strategy and abided by its commitment to suspend nuclear testing, spokeswoman Mao Ning said at a regular press conference in Beijing.

She added that China hoped the US would take concrete actions to safeguard the international nuclear disarmament and non-proliferation regime and maintain global strategic balance and stability.

North Korea is the only country that has carried out nuclear testing since the 1990s - and even Pyongyang announced a moratorium in 2018.