Lufthansa announced that its regional subsidiary Lufthansa CityLine will suspend operations beginning Saturday, citing high kerosene prices and ongoing labor disputes. The same day, KLM confirmed it had cancelled 160 flights over the next month as fuel costs continue to climb. Together, the two carriers have grounded hundreds of flights, and the head of the International Energy Agency says the worst may still be ahead.
Fatih Birol, the IEA's chief, warned that Europe has roughly six weeks of jet fuel reserves remaining if oil supplies stay disrupted. He did not mince words about what comes next.
As the Daily Mail reported, Birol said plainly:
"I can tell you soon we will hear the news that some of the flights from city A to city B might be cancelled as a result of lack of jet fuel."
The cost of jet fuel has doubled since the Middle East conflict began. A fifth of the world's oil travels through the Strait of Hormuz, which has not yet fully reopened. That bottleneck sits at the center of Europe's growing energy anxiety, and airlines are already making hard choices about which routes to fly.
British officials are not waiting for the crisis to deepen. It emerged that UK ministers are actively war-gaming for potential jet fuel shortages in roughly five to six weeks, as early as the late May bank holiday, one of the busiest travel periods of the year.
Under a worst-case scenario, emergency services aircraft, air ambulances, lifeguard helicopters, police helicopters, would receive priority access to whatever fuel remains. Officials believe fewer than 10 percent of flights would need to be cancelled if shortages materialize, and airlines have been told they must give passengers at least two weeks' notice of any cancellations.
A government spokesman offered a measured but vague response:
"We continue to engage with British airlines to support their operations against the backdrop of war in the Middle East, and to limit the impact on passengers."
Airlines UK, the industry trade body, said there is "currently" no disruption to jet fuel supplies, but acknowledged it is already in talks with the government about what happens if that changes.
"We are talking to the Government about crucial measures that will be needed to support aviation in the event of fuel disruption."
That word, "currently", is doing a lot of heavy lifting. The broader pattern across European aviation tells a more urgent story. Scandinavian Airlines has already axed 1,000 flights in April as fuel prices doubled, suggesting the cancellations at Lufthansa and KLM are not isolated events but the leading edge of a continent-wide disruption.
Paul Charles, CEO of luxury travel consultancy The PC Agency, laid out the supply problem in stark terms. Demand for air travel sits at record highs. But even an immediate end to the conflict would not fix the fuel gap quickly enough to prevent pain for travelers.
"Even if the war ended tomorrow, there would be a huge fuel gap to fill before new supplies come through. That gap simply can't be filled from other areas... and so it's likely that long-haul flights in particular would be affected quite severely."
Charles went further, describing a scenario that would be familiar to anyone who remembers the supply-chain chaos of recent years, except this time, it is not container ships sitting idle but commercial aircraft.
"Airlines will not be able to guarantee fuel at their destination, so won't be able to fly in, for fear of being stranded."
That dynamic, carriers unwilling to risk landing at airports where they cannot refuel for the return trip, could hit long-haul routes hardest. The broader energy emergency triggered by the Iran conflict has already forced countries far from the Middle East to ration fuel and mobilize reserves, a sign that aviation is just one sector feeling the squeeze.
Airports Council International Europe said its members have "increasing concerns" about jet fuel availability. The trade group warned that smaller airports are particularly vulnerable, they lack the bargaining power and storage capacity of major hubs and could face supply cutoffs first.
British suppliers have reportedly diversified their fuel purchasing to reduce exposure, but diversification only goes so far when the underlying supply is constrained at its source. The Strait of Hormuz remains a chokepoint, and no amount of contract shuffling changes the physics of a pipeline that is not flowing at full capacity.
Fuel costs are not the only headache facing European travelers. Brussels' new Entry/Exit System, automated digital border technology designed to vet tourists when they arrive and leave, became fully operational last week. The rollout has not gone smoothly.
On Sunday, airline passengers were left stranded at Milan Linate airport under the new border rules for holidaymakers from non-EU countries. Reports described passengers vomiting and passing out as delays mounted. The scene at Linate was a preview of what EU border checks may inflict on British travelers across the continent as the system expands.
Thomas Reynaert, a vice president of global aviation body IATA, did not hide his frustration with the lack of preparation:
"We are very concerned about the lack of progress in resolving problems with the EES. Unless there is action to ensure borders are adequately manned and the electronic gates and remote app are working properly, we could see passengers, including families with kids, queuing up to four hours in popular holiday destinations."
Four-hour queues at passport control, on top of cancelled flights and surging fares. For families who booked summer travel months ago, the picture is grim.
Rory Boland, editor of Which? Travel, offered practical guidance for passengers caught in the crossfire. Travelers whose package holidays or flights are cancelled should receive a refund. But those who booked hotels separately from their flights may be out of luck.
"It is always safer to book a package, otherwise you are left relying on travel insurance which often has unexpected loopholes."
That advice is cold comfort for anyone who already holds a non-refundable hotel booking in a destination their airline can no longer reach. And travel insurance, as Boland noted, is riddled with gaps that most consumers do not discover until they file a claim.
The compounding nature of these disruptions, fuel shortages, border-system failures, labor disputes, airspace restrictions tied to the Iran conflict, means travelers face a gauntlet of risks that no single booking decision can eliminate.
Strip away the airline schedules and the border-control software, and the core problem is one conservatives have warned about for years: energy dependence carries a price, and that price comes due at the worst possible time.
Europe's jet fuel reserves are measured in weeks, not months. The continent's refining capacity and supply diversity were never built to absorb a sustained disruption to Middle Eastern oil flows. When the Strait of Hormuz tightens, European airlines do not have a domestic shale boom to fall back on. They have six weeks of reserves and a government spokesman promising to "engage."
Officials estimate fewer than 10 percent of flights would need to be cut. But that estimate assumes the disruption does not worsen, an assumption that the IEA's own chief does not seem to share. And even a 10 percent cut, spread unevenly across smaller airports and long-haul routes, would strand thousands of passengers and drive fares higher still for everyone else.
The travelers left holding cancelled tickets and non-refundable hotel rooms are not policy makers. They are families, retirees, and workers who planned trips in good faith and now find themselves at the mercy of supply chains that their governments failed to secure. The people who pay the price for elite energy policy never seem to be the people who set it.
