The Doomsday Clock has remained at 100 seconds, staying the closest to midnight it has ever been for the second year running.
Maintaining last year's grim record means the clock's keepers perceived threat of global apocalypse has not cooled off in the past 12 months.
Last year the clock was moved forward by 20 seconds.
Rachel Bronson, president and chief executive of the Bulletin of the Atomic Scientists, cited the ongoing coronavirus pandemic as one of the reasons for this year's count, saying: "We recognise that humanity continues to suffer as the Covid-19 pandemic spreads around the world.
"The pandemic revealed just how unprepared and unwilling countries and the international system are to handle global emergencies properly.
"In this time of genuine crisis, governments around the world too often abdicated responsibility, ignored scientific advice, did not co-operate to communicate effectively and consequently failed to protect health and welfare of their citizens."
The countdown was established in 1947 by experts from The Bulletin of the Atomic Scientists who were working on the Manhattan Project to design and build the first atomic bomb.
The bulletin is an independent non-profit organisation run by some of the world's most eminent scientists.
It was originally intended to warn of the threat of nuclear armageddon.
However the Doomsday Clock also takes into account the likelihood of other emerging threats such as climate change, and advances in biotechnology and artificial intelligence.
