The symbolic Doomsday Clock calculated by a group of scientists was moved a minute closer to midnight on Tuesday, with the group citing inadequate progress on nuclear weapons reduction and climate change.
The clock was moved to five minutes to midnight, the Bulletin of the Atomic Scientists said, the first adjustment since the beginning of 2010, when it was moved back one minute to six minutes from midnight -- or "doomsday".
"Two years ago, it appeared that world leaders might address the truly global threats that we face. In many cases, that trend has not continued or been reversed," the group said in a statement.
The Bulletin (www.thebulletin.org) is a periodical founded in 1945 by University of Chicago scientists who had helped develop the first atomic weapons in the Manhattan Project.
They created the Doomsday Clock two years later to symbolize how close humanity was to self-annihilation, with an initial setting of seven minutes to midnight. Initially the clock was focused on nuclear war, but it has been broadened in recent years as the scientists, who include a range of Nobel laureates, added other risks to humanity.
The scientists said world leaders had failed to sustain the progress in nuclear disarmament that had seen them move the hands back on the clock two years ago.