"We are strongly against interference in each other's interests ... Let there be no doubt that we will act decisively in this regard," he said.
"But this does not mean that we somehow want to distance ourselves or further worsen the already deteriorating relationship between Moscow and Brussels. On the contrary, we are interested in its development," he added.
Peskov's comments came a day after Josep Borrell, the EU's high representative for foreign affairs and security policy, made pessimistic remarks on Russia-EU ties.
"My meeting with (Russian Foreign) Minister Lavrov and the messages sent by Russian authorities during my visit confirmed that Europe and Russia are drifting apart," Borrell said following his trip to Moscow from Feb. 4 to 6.