Banks in Japan and Europe are fed up with central bank negative interest rate policies that cost the banks money.

Commercial banks and their customers alike seek ways to avoid central bank lunacy.

In Germany, banks are considering holding deposits in cash rather that parking funds at the ECB.

The Financial Times reports Negative Rates Stir Bank Mutiny.

Lenders in Europe and Japan are rebelling against their central banks' negative interest rate policies, with one big German group going so far as to weigh storing excess deposits in vaults.

The move by Commerzbank to consider stashing cash in costly deposit boxes instead of keeping it with the European Central Bank came at the same time as Tokyo's biggest financial group warned it was poised to quit the 22-member club of primary dealers for Japanese sovereign debt.

The ECB and the Bank of Japan have for months imposed negative rates for holding bank deposits in an attempt to push lenders to deploy their cash in the real economy through more aggressive lending to businesses. The policy in effect taxes banks for storing excess liquidity.

The central bank policies have hit bank profitability in both regions and German banks have been vocal in criticising Mario Draghi, ECB president, accusing him of punishing savers and undermining their business models. The policy cost German banks €248m last year, according to the Bundesbank.