• Tests ensure all parts can function to set up nuclear blast.
• Aim is to confirm that new weapons outperform older designs.
• Trump ordered testing after 33 years, signalling China, and Russia.

The nuclear weapons testing ordered by US President Donald Trump will not involve nuclear explosions at this time, Energy Secretary Chris Wright said on Sunday.

“I think the tests we’re talking about right now are system tests,” Wright said in an interview with Fox News. “These are not nuclear explosions. These are what we call non-critical explosions.”

The testing involves all the other parts of a nuclear weapon to make sure they are functioning and can set up a nuclear blast, said Wright, whose agency is responsible for testing US nuclear weapons.

The tests will be carried out on new systems to help ensure replacement nuclear weapons are better than previous ones, Wright said on Fox News‘ “The Sunday Briefing.”

Just before he met with Chinese leader Xi Jinping in South Korea on Thursday, Trump said he ordered the US military to immediately restart the process for testing nuclear weapons after a halt of 33 years, a move that appeared to be a message to rival nuclear powers China and Russia.

He reaffirmed his comments on Friday but did not answer directly when asked whether that would include underground nuclear tests that were common during the Cold War.

The United States conducted nuclear test explosions in the 1960s, 1970s and 1980s, Wright said, and collected detailed information and measurements on the blasts.

“With our science and our computation power, we can simulate incredibly accurately exactly what will happen in a nuclear explosion,” Wright said.

“Now we simulate what were the conditions that delivered that, and as we change bomb designs, what will they deliver?”

A powerful 6.3-magnitude earthquake rattled Afghanistan’s Hindu Kush region on Monday, the US Geological Survey reported, raising concerns over possible casualties and damage in the mountainous area.

The earthquake hit at a depth of 28km (17.4 miles) and its epicentre was 22.5km from a town called Khulm, which has a population of nearly 65,000, according to USGS.

The country’s national disaster management agency said reports on casualties and damage would be shared later. 

Reuters could not immediately verify the extent of damage from the earthquake.

More than 1,000 people died after an earthquake hit Afghanistan in August, according to the Afghan Red Crescent Society, a humanitarian group working in the region.

This is a developing story that is being updated with additional information

India launched its heaviest ever communication satellite on Sunday, the latest step in the country’s ambitious space programme.

The CMS-03 satellite blasted off from Sriharikota in the southern state of Andhra Pradesh at 5:26 pm (1156 GMT).

“Our space sector continues to make us proud!” said Prime Minister Narendra Modi, who wants to send an Indian astronaut to the Moon by 2040.

Weighing about 4,410 kilograms (9,722 pounds), it is “the heaviest communication satellite” launched in the country, the Indian Space Research Organisation said on Thursday.

The Indian Navy said the satellite would help “secure communication links between ships, aircraft, submarines”.

The CMS-03 satellite was sent into orbit from the towering 43.5 metre (143 foot) tall LVM3-M5 launch vehicle.

It is an upgraded version of the rocket that launched India´s unmanned craft that landed on the Moon in August 2023.

Only Russia, the United States and China have previously achieved a controlled landing on the lunar surface.

The country has flexed its spacefaring ambitions in the last decade, with its space programme growing considerably in size and momentum.

Shubhanshu Shukla, a test pilot with the Indian Air Force, this year became the second Indian to travel to space and the first to reach the International Space Station— a key step towards India’s own crewed mission planned for 2027.