Set by top scientists and security experts, the timing of the clock remains the same as last year and the closest it has ever been to midnight in its more than 75-year-history.

"Trends continue to point ominously towards global catastrophe," said Rachel Bronson, president and CEO of the Bulletin of Atomic Scientists. "The war in Ukraine poses an ever present risk of nuclear escalation, and the October 7 attack in Israel and war in Gaza provides further illustration of the horrors of modern war, even without nuclear escalation.

Rather than abandoning nuclear weapons, countries that possess them are upgrading their arsenals and threatening to create a new arms race, while massive floods, fires and other disasters marked the hottest year on record by far, with little meaningful action on climate change.

"Biological research aimed at preventing future pandemics has proven useful, but also presents the risks of causing one," she said, while recent advances in artificial intelligence (AI) raise questions about how to control a technology "that could improve or threaten civilization in countless ways."

The clock was originally set at seven minutes to midnight.

The furthest from midnight it has ever been is 17 minutes, following the end of the Cold War in 1991.

The Bulletin was founded in 1945 by Albert Einstein, J. Robert Oppenheimer and other scientists who worked on the Manhattan Project, which produced the first nuclear weapons. The idea of the clock symbolizing global vulnerability to catastrophe followed in 1947.