U.N. Secretary-General Antonio Guterres is to launch a major push for disarmament talks covering everything from nuclear and cyber war to small arms, braving certain U.S. resistance to such bold initiatives, officials and experts said.

Guterres aims to forestall a new nuclear arms race and get the big powers back into negotiations after two decades of stalemate, according to a Geneva-based expert familiar with the plans who requested anonymity.

The expert said Guterres also wants to end "state-led paralysis" in talks on cyberwarfare and robotics by getting the private sector involved, and to start talks on use of explosives in urban areas and curbing access to conventional weapons, the biggest killer.