The Kremlin said on Sunday that any supply of long-range missiles to Kyiv by France and Germany would lead to a further round of "spiralling tension" in the Ukraine conflict.
Britain last month became the first country to supply Ukraine with long-range cruise missiles.
Ukraine has asked Germany for Taurus cruise missiles, which have a range of 500 km (311 miles), while President Emmanuel Macron has said France will give Ukraine missiles with a range allowing it to carry out its long-anticipated counteroffensive.
"We are already starting to see discussions about deliveries from France and Germany of missiles with a range of 500 km or more," Kremlin spokesman Dmitry Peskov told a reporter from the Rossiya-1 TV channel.
"This is a completely different weapon which will lead to, let's say, another round of spiralling tension," he said.
Russia has repeatedly criticised Western countries for supplying Ukraine with weapons and has warned that NATO members have effectively become direct parties to the conflict.
Moscow has made clear it sees such weapons supplied by the West as legitimate targets in what it calls its "special military operation" in Ukraine, now in its 16th month.
Ukraine says it needs more weapons, including long-range missiles, to defend itself against Russian attacks and re-capture its occupied territory.
Peskov also reiterated that Russia would continue its operations in Ukraine until the "job is done... There is no alternative".
Moscow says it had to act in Ukraine to protect its own security and push back against what it says is a hostile and aggressive West bent on the destruction of Russia.
Kyiv and its Western allies say Russia is waging an unprovoked war of aggression and a land grab in Ukraine.
