Russia, the world’s biggest nuclear power, has started updating its nuclear doctrine, Kremlin spokesman Dmitry Peskov said Monday, citing an earlier statement by President Vladimir Putin.

“President Putin has said that work is under way to bring the doctrine into line with current realities,” Peskov told a briefing, without elaborating.

A senior member of the Russian parliament said on Sunday that Moscow could reduce the decision-making time stipulated in official policy for the use of…