BIS Review 15/2010  1  In a liquidity crisis, monetary authorities can engage in foreign currency liquidity-providing operations which can be classified into the following four major concepts: national foreign exchange reserves, pooling of reserves, inter-central bank swap lines or repos and monetary units or loan facilities by supra-national monetary authorities.
Central banks maintain foreign reserves mainly in key currencies but also in high-value liquid assets like gold. They may redirect the investments of such foreign reserves towards bank deposits, in an endeavor to offset the withdrawal of bank deposits in foreign currency by investors.