Trump says nuclear weapons testing will resume in the US after more than 30 years

President Donald Trump has urged US military leaders to resume nuclear weapons tests to keep pace with other countries such as Russia and China.

“Due to the testing programs of other countries, I have instructed the War Department to begin testing our nuclear weapons on an equal footing,” he wrote on social media just before a meeting with Chinese President Xi Jinping in South Korea.

The US has more nuclear weapons than any other country, Trump said, with Russia a close second and China a “distant third”. It has not conducted a nuclear test since 1992.

It comes just days after Trump condemned Russia for testing a nuclear-powered missile. The Kremlin says its tests are “not nuclear”.

Later, on Air Force One after the two leaders met, Trump said the nuclear test sites would be determined later.

“As others are testing, I think it’s appropriate that we do as well,” Trump said on his way back to Washington.

According to the Arms Control Association (ACA), no country other than North Korea has conducted a nuclear test explosion this century — and even Pyongyang announced a moratorium in 2018.

Trump’s announcement did not make it clear whether he was referring to testing a nuclear explosion or simply a weapons system that would be capable of delivering a nuclear weapon.

His post Wednesday night acknowledged the “enormous destructive power” of nuclear weapons but said he had “no choice” but to update and renew America’s arsenal during his first term.

He also said that China’s nuclear program “will be leveled within 5 years”.

The announcement marks an apparent reversal in longstanding US policy. The last US nuclear test was in 1992, before former Republican President George HW Bush imposed a moratorium after the end of the Cold War.

Russia announced over the weekend that it had successfully tested two new weapons capable of carrying nuclear warheads.

These include a missile that the Kremlin says can penetrate US defense systems and an underwater drone called the Poseidon capable of striking the US west coast and triggering radioactive ocean waves. But these tests do not involve the detonation of nuclear weapons.

On Thursday, Russia denied conducting nuclear tests.

“Regarding the tests of Poseidon and Burevestnik, we hope that the information was conveyed correctly to President Trump,” Kremlin spokesman Dmitry Peskov told reporters. “This cannot in any way be interpreted as a nuclear test.

The Kremlin said the United States had not notified Russia of its intention to conduct nuclear weapons tests.

“The United States is a sovereign country that has the right to make its own sovereign decisions. But I want to recall President Putin’s statement, which has been repeated many times: if anyone deviates from the moratorium, Russia will act accordingly,” the spokesman said.

China also responded to Trump’s statement, saying it hoped the US would seriously fulfill its obligations under the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and fulfill its commitment to end nuclear tests.

Trump said the US has more nuclear weapons than any other country.

The exact number of warheads possessed by each country is kept secret in any case – but Russia is believed to have a total of about 5,459 warheads, while the US has about 5,177, according to the Federation of American Scientists (FAS).

The US-based ACA gives slightly higher estimates, saying America’s nuclear stockpile is about 5,225 warheads, while Russia has roughly 5,580.

China is the third largest nuclear power with about 600 warheads, France has 290, the United Kingdom 225, India 180, Pakistan 170, Israel 90 and North Korea 50, FAS reports.

According to the US think tank Center for Strategic and International Studies (CSIS), China has roughly doubled its nuclear arsenal in the past five years and is expected to exceed 1,000 weapons by 2030.

Trump’s announcement about the nuclear tests came about 100 days before the New Strategic Arms Reduction Treaty (New Start) expires in February 2026 – the last remaining nuclear weapons treaty between the US and Russia.

The agreement limits each country to 1,550 warheads on deployed missiles capable of crossing continents.

The last time the US tested a nuclear bomb was on September 23, 1992. The test took place in an underground facility in the western state of Nevada.

The project, codenamed Divider, was the 1,054th nuclear weapon test conducted by the US, according to the Los Alamos National Laboratory, which played a central role in helping develop the world’s first atomic bomb.

The Nevada Test Site, 65 miles (105 km) north of Las Vegas, is still operated by the US government.

“If deemed necessary, the site could be reauthorized for nuclear weapons testing,” according to the National Museum of Nuclear Science and History, which is an affiliate of the Smithsonian Institution.

But some experts note that it will take at least 36 months for the US to resume underground nuclear testing at the former Nevada test site.

“Trump is misinformed and out of touch,” Daryl G. Kimball, executive director of ACA, wrote to X. “The United States has no technical, military or political justification for resuming nuclear explosive tests for the first time since 1992.”

“Trump will provoke strong public opposition in Nevada from all of the US’s allies, and this could trigger a chain reaction of nuclear tests by the US’s adversaries and destroy the Nuclear Non-Proliferation Treaty,” Mr Kimball added.

Trump’s announcement also drew backlash from several opposition Democrats. Representative Dina Titus of Nevada wrote to X: “I will introduce legislation to end this.”

The US first entered the nuclear age with the test of the first atomic bomb, the Trinity, in July 1945 in the desert of Alamogordo, New Mexico.

It later became the only country in the world to use nuclear weapons in war after dropping two atomic bombs on the Japanese cities of Hiroshima and Nagasaki in August of that year during World War II.

Approximately 140,000 people were killed in Hiroshima and 74,000 in Nagasaki, with many deaths occurring from the immediate effects of the blast, burns and later from radiation sickness.