Leaders of the bloc's 27 member countries agreed at a summit in Brussels to move ahead with work on the plan, presented this week by the EU's executive body, the European Commission.

Commission President Ursula von der Leyen said the first 1 billion euros from the scheme could be disbursed as soon as July 1.

The Commission estimated the profits on the assets - various Russian central bank securities and cash - could be between 2.5 billion euros and 3 billion euros per year.

Some Western banks fear, however, that they might later be held liable by Russia if they are involved in any transfer of money to Ukraine and that the EU plan could be extended to assets in accounts they hold for sanctioned individuals and companies.

The Kremlin on Friday said Western banks' legal departments understand the "catastrophic consequences" that would follow should the EU proceed with plans to confiscate Russian assets.