The Bulletin of the Atomic Scientists, an advocacy group, uses a clock to symbolize the likelihood of people doing something to end humanity.

Representatives from the Bulletin of the Atomic Scientists reveal an updated Doomsday Clock during a press briefing at the Carnegie Endowment for International Peace in Washington, D.C., on Jan. 23.Pablo Martinez Monsivais / AP

Earth is closer than it`s ever been to destruction as Russia, China, the U.S. and other countries become "increasingly aggressive, adversarial, and nationalistic," a science-oriented advocacy group said Tuesday and advanced its "Doomsday Clock" to 85 seconds till midnight.

The Bulletin of the Atomic Scientists cited risks of nuclear war, climate change, potential misuse of biotechnology and the increasing use of artificial intelligence without adequate controls as it made the annual announcement, which rates how close humanity is from ending.

Last year, the clock advanced to 89 seconds to midnight.

Since then, "hard-won global understandings are collapsing, accelerating a winner-takes-all great power competition and undermining the international cooperation" needed to reduce existential risks, the group said.

They worry about the threat of escalating conflicts involving nuclear-armed countries, citing the Russia-Ukraine war, May`s conflict between India and Pakistan and whether Iran is capable of developing nuclear weapons after strikes last summer by the U.S. and Israel.

International trust and cooperation is essential because, "if the world splinters into an us-versus-them, zero-sum approach, it increases the likelihood that we all lose," said Daniel Holz, chair of the group`s science and security board.

The group also highlighted droughts, heat waves and floods linked to global warming, as well as the failure of nations to adopt meaningful agreements to fight global warming - singling out U.S. President Donald Trump`s efforts to boost fossil fuels and hobble renewable energy production.

Starting in 1947, the advocacy group used a clock to symbolize the potential and even likelihood of people doing something to end humanity. At the end of the Cold War, it was as close as 17 minutes to midnight. In the past few years, to address rapid global changes, the group has changed from counting down the minutes until midnight to counting down the seconds.

The group said the clock could be turned back if leaders and nations worked together to address existential risks.