A new debate is emerging within the European Central Bank (ECB) over whether commercial banks should face additional financial costs as policymakers attempt to control inflation and manage the central bank's growing losses.

Pierre Wunsch, governor of the National Bank of Belgium and a member of the ECB's Governing Council, has questioned proposals to increase the proportion of bank reserves that earn no interest.

Speaking at a conference in Brussels on 8 October 2026, Wunsch warned that the measure could damage confidence in future monetary policy operations and blur the boundaries between central banking and government financial policy.

His comments highlight a difficult challenge for European policymakers as higher interest rates place increasing pressure on the financial system.

Why Is The ECB Considering Higher Charges?

The proposal focuses on the minimum reserve requirement, a rule determining how much money commercial banks must hold in accounts with their central bank.

These mandatory reserves currently earn no interest. Some ECB policymakers are considering increasing the required proportion, effectively forcing banks to keep more money in accounts that provide no financial return. Supporters of the idea see two potential benefits.

First, it could reduce the interest expenses faced by the ECB and national central banks. Second, it could help tighten financial conditions while inflation remains elevated. However, the proposal has generated disagreement over whether such a measure would be appropriate or effective.

How Did Central Banks Accumulate So Much Money?

The issue dates back to the years following Europe's financial and economic crises. During the decade before the COVID-19 pandemic, the ECB purchased enormous quantities of government and other bonds to support economic activity and prevent borrowing costs from becoming excessively high.

These purchases injected trillions of euros into the banking system. At the time, interest rates were extremely low or even negative, making the strategy relatively inexpensive. Conditions have since changed considerably.

As the ECB raises interest rates to tackle inflation, it must pay commercial banks more interest on eligible deposits held at the central bank. This creates substantial expenses, particularly because the banking system still holds more than €2.1 trillion in excess liquidity.

Why Is Germany Particularly Exposed?

Germany's Bundesbank has been especially affected by the financial consequences of higher interest rates. The central bank accumulated significant assets during earlier bond-purchasing programmes, while its interest expenses have increased sharply. These pressures have contributed to financial losses and forced it to suspend dividend payments to the government.

The institution may remain unable to resume such payments until the next decade. Increasing unremunerated reserve requirements could help reduce these expenses, although it would also transfer more of the financial burden to commercial banks.

Why Does Pierre Wunsch Oppose The Proposal?

Wunsch believes the reasoning behind higher minimum reserve requirements remains insufficiently convincing. His central concern is that using reserve rules to reduce central bank losses could effectively turn a monetary policy instrument into a form of taxation. He described this possibility as a quasi-fiscal measure, arguing that decisions involving the collection and distribution of public financial resources normally belong to governments.

The distinction matters because central banks are expected to make monetary policy decisions independently, primarily to maintain price stability. Using banking regulations to improve their own financial results could raise questions about the purpose of those decisions.

Could Future ECB Programmes Be Affected?

Wunsch also highlighted a potential longer-term consequence. Commercial banks play an important role in transmitting monetary policy and participating in central bank operations. If banks believe that funds received through future ECB programmes could later become subject to additional financial burdens, their willingness to participate may decline.

This could make future bond-purchasing operations less effective. The concern is particularly relevant because central banks may need to introduce similar measures again during future economic crises.

What Happens Next?

The discussion comes as the ECB continues raising interest rates in response to persistent inflation. Higher rates increase borrowing costs for households and businesses while simultaneously adding to central banks' interest expenses. Policymakers must therefore decide whether adjusting reserve requirements would support monetary stability or introduce unnecessary complications.

No final decision on increasing the minimum reserve ratio has been announced. The debate illustrates how measures introduced during an era of exceptionally low interest rates can create new financial challenges when economic conditions change.

For Europe's banking system, the outcome could influence profitability, liquidity management and the relationship between commercial banks and monetary authorities.