A western coalition including the U.S., the European Union, Canada and the U.K. is to cut off some Russian banks from the SWIFT interbank payment system.
A decisive move towards negative deposit rates could get the interbank market working again throughout the euro area, argues Christel Aranda-Hassel, an economist at Credit Suisse.
In September yields on some short-term bonds, half of which are on the ecb's balance-sheet, fell 1.1 percentage points below interbank interest rates, to their lowest since the euro-zone crisis.
Imports have collapsed partly because sanctions on the Russian central bank and the expulsion of some lenders from the swift interbank messaging network have made it harder for consumers and firms to buy Western goods.