The Kremlin hit out Wednesday at the "unpredictability" of the United States under the Trump administration, saying it was causing "deep global concern".
"The fact that America has become unpredictable lately is no secret to anyone," Kremlin spokesman Dmitry Peskov told Dozhd TV during a visit by President Vladimir Putin to a regional summit in Singapore.
"Such unpredictability from the largest country, the most powerful economy in the world, is the subject of deep global concern," he added.
Peskov's comments come two weeks ahead of a slated face-to-face between President Donald Trump and Putin at a G20 summit in Argentina.
Relations between the two countries have hit new lows with American officials planning to roll out fresh sanctions against Moscow in response to the botched poisoning of former Russian spy Sergei Skripal in Britain.
Western governments have accused Russia of being behind the plot which saw Skripal and his daughter poisoned with a nerve agent. Two British citizens were also poisoned, one of whom died.
Moscow has denied being behind the brazen hit and has condemned efforts to sanction it over the incident.
"We do not recognise these unilateral restrictions... and we consider them illegitimate," Peskov said of the threatened sanctions, adding they would only "further complicate" Russia-US relations.
World leaders are currently meeting in Singapore, which is hosting the annual Association of Southeast Asian Nations (ASEAN) summit.
Trump is not at the gathering and has sent Vice President Mike Pence instead.
Peskov said "no separate meeting" was currently planned between Putin and Pence. But he added that there was no need for a face-to-face given Trump and Putin will soon meet in Buenos Aires.
'Such unpredictability from the largest country, the most powerful economy in the world, is the subject of deep global concern,' Kremlin spokesman Dmitry Peskov said.