ECB Exposes Banks’ Geopolitical Blind Spot: Stress Tests Reveal Dangerous Liquidity Gaps

What would happen to a European bank if the Strait of Hormuz were closed, energy prices surged, the war in Ukraine escalated or a major cyberattack knocked out critical infrastructure?

And, more importantly, how quickly could a geopolitical shock move from the real economy into the banking system itself?

The European Central Bank tried to answer those questions in an unusual way.

In its first geopolitical reverse stress test, 110 directly supervised euro-area banks were not given a common adverse scenario by Frankfurt. Instead, they were asked to design the geopolitical crisis that would be most damaging to their own business model.

The ECB gave them only the end point: a 300-basis-point fall in the Common Equity Tier 1, or CET1, capital ratio.

The banks then had to explain what combination of war, energy disruption, trade fragmentation or security threats could produce that loss — and through which transmission channels.

And that is where the weaknesses began to emerge.

Most banks were able to model substantial capital losses.

They were far less convincing, however, when it came to explaining what would happen to liquidity and funding conditions once that capital erosion began.

The ECB changed the rules: “Tell us what could break you”

The 2026 exercise worked in reverse.

In a conventional stress test, the ECB or the European Banking Authority provides a common macroeconomic shock and measures how institutions perform under it.

This time, Frankfurt defined the capital outcome and effectively asked banks to identify the geopolitical sequence that could take them there.

The target was a decline of at least 300 basis points in CET1 over the three-year scenario horizon.

That allowed supervisors to test something deeper than raw capital resilience.

It revealed how bank management teams themselves understand geopolitical risk.

From Hormuz and Ukraine to Taiwan and cyber warfare

The scenarios constructed by the banks covered a wide range of threats.

Military conflict.

Energy disruption.

Trade wars.

Breakdowns in global supply chains.

Cyberattacks.

Strikes against critical infrastructure.

The ECB found that when scenarios involved military escalation and cyber threats, the security channel — including physical, cyber and hybrid risks — became a major mechanism through which the shock reached bank balance sheets.

That matters particularly in the current environment.

The ECB has already warned that Middle East energy disruptions create upside risks to inflation and downside risks to growth, while bank exposures to energy-intensive and trade-sensitive companies can translate geopolitical shocks into credit, funding and liquidity risks.

The real blind spot: Capital and liquidity do not live in separate worlds

This was the most important finding of the exercise.

Several banks were able to show severe capital deterioration without modelling a correspondingly severe deterioration in liquidity.

The ECB considers that problematic.

In a real crisis, solvency and liquidity interact.

When a bank loses capital, its credit profile can weaken.

Funding costs can rise.

Market access can deteriorate.

Collateral requirements can increase.

And depositors or investors can change their behaviour.

That means a capital shock can quickly become a funding shock.

The ECB found that some banks showed surprisingly limited deterioration in liquidity indicators despite the deliberately severe capital loss embedded in the exercise.

This is now one of the areas supervisors intend to examine more closely.

The lesson from 2023: Liquidity can disappear very quickly

This is not an academic concern.

The banking turmoil of 2023 demonstrated how rapidly questions about a bank’s financial health can become a crisis of confidence and funding.

In a world of digital banking, deposits can move far faster than traditional models of deposit outflows once assumed.

That makes the ECB’s finding systemically important.

A bank may appear adequately capitalised in a model and still face severe problems if markets stop funding it on the terms that model assumes.

Banks understood the credit risk — and rightly so

The exercise was not a complete failure.

The ECB said most institutions were able to develop economically meaningful geopolitical scenarios tailored to their real exposures.

Credit risk and falling profitability were among the main transmission mechanisms through which geopolitical shocks damaged bank balance sheets.

Manufacturing, energy and transport were among the sectors most frequently identified as vulnerable.

Banks with large markets businesses also modelled losses from weaker trading activity and lower fee income.

The key point is that geopolitical risk does not have to hit a bank directly.

It can hit the bank’s customers first.

Hormuz: How one chokepoint can end up on a bank balance sheet

The Strait of Hormuz illustrates the transmission mechanism clearly.

A serious disruption to energy flows can push oil and gas prices sharply higher.

Higher energy costs squeeze industrial profit margins.

Shipping and transport companies face more expensive fuel, higher insurance premiums and disrupted routes.

Households lose disposable income.

Companies require more working capital.

As the real economy weakens, credit quality deteriorates.

The ECB has already warned that current geo-economic and energy shocks can test the ability of companies and households to service their debts.

A geopolitical disruption thousands of kilometres from Frankfurt can therefore ultimately end up as a non-performing loan inside the euro area.

The second red flag: Banks assumed they could save themselves

Another important finding concerned the management actions banks assumed they would take during a crisis.

Institutions projected that they could respond by selling businesses or portfolios, raising capital, cutting costs and reducing shareholder distributions.

The ECB did not say those measures were inherently unrealistic.

But supervisors found cases of assumptions that appeared overly optimistic — for example, the idea that loan portfolios could be sold at ambitious prices during stressed markets or that new capital could be raised on favourable terms.

That creates a classic systemic-crisis problem.

One bank may be able to sell assets.

What happens when dozens of banks try to sell at the same time?

The “everyone heading for the exit” problem

If many banks simultaneously try to reduce risk, the very act of protecting themselves can deepen the crisis.

Large-scale asset sales depress prices.

Credit tightening removes financing from companies.

Businesses then cut investment and employment.

The downturn deepens.

And credit losses return to the banks.

That is why the ECB is placing particular emphasis on whether management actions remain realistic during a system-wide shock rather than a problem affecting one institution in isolation.

Cyber: Geopolitical conflict no longer needs tanks

The exercise also highlighted a different type of geopolitical warfare.

Cyberattacks.

Cyber incidents and disruptions involving critical external service providers were among the most important non-financial threats included in banks’ scenarios.

That changes the nature of geopolitical banking risk.

A successful attack does not need to target a bank branch.

It can strike a cloud provider.

A telecoms network.

A payments system.

An energy facility.

Or a critical technology supplier serving multiple banks at the same time.

The concentration of essential technological services among a limited number of providers therefore creates potential common points of failure.

Foreign-currency liquidity is another weak point

The vulnerabilities became even clearer in foreign-currency funding.

Some banks showed limited or virtually no deterioration in foreign-currency liquidity indicators, despite modelling severe geopolitical shocks.

In individual cases, foreign-currency liquidity coverage ratios fell below the 100% regulatory threshold.

That matters because geopolitical crises can create sudden demand for dollars, widen cross-currency funding costs and make short-term refinancing far more difficult.

Banks with large foreign-currency liabilities and insufficient matching liquid assets are particularly exposed.

ECB sceptical about liquidity resilience

Across the banking system, headline liquidity buffers still appeared comfortable in the banks’ own calculations.

The median Liquidity Coverage Ratio fell from 186% at the starting point to 163% after the first year of stress.

The interquartile range moved from 175%-204% to 150%-185%.

At first glance, those numbers suggest a system with substantial liquidity protection.

The ECB’s concern is the limited sensitivity of the liquidity metrics to such a severe capital shock.

A three-percentage-point CET1 decline could affect credit ratings, bond issuance costs, secured funding markets and depositor behaviour far more aggressively than some models assumed.

That gap between capital deterioration and funding pressure is at the heart of Frankfurt’s concerns.

Energy, transport and industry are on the front line

The largest real-economy impacts appeared in sectors including manufacturing, transport, energy-intensive activity and other businesses heavily exposed to global trade and energy prices.

That creates a particularly important link between geopolitics and banking risk.

An energy shock hurts companies first.

Companies then draw down credit lines, suffer weaker margins or default.

Banks absorb the consequences.

The same dynamic applies to shipping, logistics and international supply chains.

Disruption increases freight costs, insurance premiums and delivery times while reducing the value and predictability of commercial claims.

Commercial and retail banking activities therefore emerged among the areas most frequently affected, mainly through credit deterioration and funding pressure.

The findings now enter the supervisory process

The exercise was not a pass-or-fail test and it will not automatically produce higher capital requirements.

The ECB has said the results will not, by themselves, alter Pillar 2 Guidance.

But the findings will feed qualitatively into the Supervisory Review and Evaluation Process, or SREP.

Joint Supervisory Teams will also conduct targeted follow-up with institutions where significant weaknesses were identified.

That means gaps that initially appeared as “modelling weaknesses” can ultimately translate into real supervisory demands for stronger governance, contingency planning and risk management.

The political tension: Lighter regulation as risks become more complex

There is also a broader European debate behind the exercise.

European policymakers are under pressure to simplify regulation and reduce compliance burdens on banks as part of the EU’s wider competitiveness agenda.

At the same time, the ECB has repeatedly insisted that simplification cannot mean weaker resilience.

The reverse stress test makes that debate considerably more difficult.

Europe is discussing how to make banking supervision lighter just as the risks banks must manage are becoming more complex, interconnected and geopolitical.

The issue is no longer simply whether a bank has enough capital against conventional credit losses.

It is whether its models can capture a chain reaction beginning with war, energy, cyber disruption or trade fragmentation and ending with disappearing funding.

The biggest risk may be the one that is not properly inside the model

The ECB’s first geopolitical reverse stress test did not show that European banks are on the verge of crisis.

That would be the wrong conclusion.

The ECB itself found that banks were generally able to develop meaningful scenarios and that aggregate liquidity positions remained above regulatory minima in most cases.

But the exercise revealed something more subtle — and potentially more important.

European banks can imagine the war.

Not all of them can yet model with equal reliability the funding panic that could follow.

That is the real geo-economic warning.

The next banking shock does not have to begin with a housing bubble or a portfolio of bad loans.

It could begin in Hormuz, Taiwan, an energy terminal or a data centre — and then move through energy prices, trade, corporate balance sheets, markets and confidence before arriving on the balance sheet of a European bank.