Russia says US assumptions about the possibility of a limited nuclear conflict are “erroneous,” warning that any use of nuclear weapons could result in a global catastrophe.

White House national security adviser Jake Sullivan has said the United States will “respond decisively” if Putin orders the use of nuclear weapons in Ukraine.

The United States has privately warned Russia for several months of "consequences" for any use of nuclear weapons in Ukraine, according to American officials.

Any Russian weapons, including strategic nuclear weapons could be “used for such protection,” Medvedev said.

countries like the US believe they are entitled to have nuclear weapons.

Iran once again raises alarm over Israel's nuclear stockpile, criticizing the UN for its lack of progress for the 2010 action plan on the Middle East free of nuclear weapons.

North Korea has criticized UN Secretary-General over his remarks in support of Pyongyang’s complete denuclearization.

The US may try to use the persisting security crisis in Ukraine as a pretext to deploy armaments -- including nuclear weapons -- in space, Russia’s deputy UN envoy has warned.

Iran's UN ambassador says US failure to give assurance about Tehran’s enjoyment of full economic benefits of the 2015 deal is the main obstacle to its revival.

Russia has dismissed the "utterly unfounded" speculations that it may use nuclear weapons in Ukraine, saying it would only use its nuclear arsenal in response to "direct aggression" by NATO countries over the ongoing conflict in the former Soviet state.