European Commission President Mario Draghi said on Thursday that from a purely financial standpoint the crisis in Ukraine should not have much impact on the euro zone.
But he added that there was potential for far greater instability spreading from the nearby region if the situation escalates.
"If we look (at the situation in Ukraine) from a purely technocratic viewpoint and we look at the amount of trade in goods, services, and financial services and ... capital flows, we have to say that the interconnections are not as important as to suggest a strong contagion from that region," Draghi told a news conference.
"However, let me also add that this would be a limited way to look at the situation because the geopolitical risks in the area could quickly become substantial and generate developments that are unforeseeable and potentially of great consequence."
Crimea's parliament voted to join Russia on Thursday and its Moscow-backed government set a referendum within 10 days on the decision in a dramatic escalation of the crisis over the Ukrainian Black Sea peninsula.
(Editing by Jeremy Gaunt)