Speculation has mounted in recent days that Pyongyang is preparing to fire a trial nuke or missile on Saturday.
"Moscow is watching with great concern the escalation of tensions on the Korean peninsula," Kremlin spokesman Dmitry Peskov told journalists.
"We call for restraint from all countries and warn countries not to pursue actions that could consist of any provocative steps," he added.
Speculation has mounted in recent days that Pyongyang is preparing to fire a trial nuke or missile when it marks a major anniversary on Saturday, prompting US President Donald Trump to pledge the matter "will be taken care of."
Trump has sent an aircraft carrier-led strike group to the Korean peninsula to press his point, in one of a series of signals indicating his willingness to shake up foreign policy strategy.
Russia's North Korea envoy Alexander Matsegora on Friday said he does not rule out a test or launch in the near future, expressing concern that Trump could take a fateful decision without any North Korea experts on his team.
"If Mr. Trump would listen to a Russian Korea expert with 40 years of experience, I would advise him not to do it," he told RIA-Novosti of a potential US strike.
"Right now we all must stop at the edge of the abyss and not take this fateful step," he said.