Nuclear sharing has nonnuclear NATO members deploy US nuclear weapons in their countries and operate them jointly with the US.
Experts say Kim Jong Un is likely to conclude that nuclear weaponry is the most reliable way to maintain his control, in light of Ukraine.
In addition to North Korea’s recent missile launch, China and Russia have stepped up activity in the waters and airspace around Japan.
Putin also ordered Russia's deterrence forces to be placed on "a special mode of combat duty" in a meeting with top officials.
Russia's defence ministry previously said its nuclear missile forces had been placed on enhanced combat duty.
Pyongyang also said it will “operate a military reconnaissance satellite in the near future.
Victims of the hacking tool included high-level, non-western government agencies in Asia and Africa.
While Mr Putin's order does not mean he is ordering Russia to prepare for a nuclear strike, it raised concern.
Russian troops took over the power plant while Ukrainian forces battled them on three sides on Thursday (Feb 24).
Disinformation posts were first circulated in pro-Russian groups, and then relayed by the state and pro-Kremlin media to the world.