Brussels on Friday began an in-depth investigation into a proposed restructuring of ailing Belgian-French bank Dexia and its planned €6.4bn ($8.2bn) capital injection, to ensure that EU state aid rules are not being breached.

The move is the first in what will undoubtedly be a long list of lengthy bank probes by the European Commission, following the emergency help doled out by governments last autumn when financial turmoil was at its height.