Belgian bank Fortis has suffered a €295m ($412m) loss from recent foreign exchange market swings, which wiped out the value of its currency portfolio that it had built up to ease its takeover by French bank BNP Paribas, a deal that stalled earlier this month.

Fortis became the subject of a takeover by BNP Paribas on October 6, after falling into trouble at the end of September when the Benelux governments were forced to inject more than €11bn to rescue the bank.