The European Central Bank Governing Council was given an in-depth analysis of the risks posed by potential Russian military aggression in eastern Europe at the start of its last rate-setting meeting, according to people familiar with the discussion.

Policymakers started their April 16-17 gathering in Frankfurt with a seminar presented by academics detailing scenarios on how such an attack on the Europe Union might plausibly materialize within four years, said the people, who declined to be identified because the session was private.