British holidaymakers are poised to receive warnings from ministers urging them to brace for possible flight cancellations. The expected alert comes amid airline bosses raising concerns over potential jet fuel supply shortages that could hit the UK from next month onwards.

Transport Secretary Heidi Alexander is understood to be preparing to “level with” the public this weekend regarding the probability of disruption and cancellations throughout the summer period. She is also set to set out contingency plans aimed at limiting the impact, with six holiday destinations reportedly identified as facing cancellation risks.

Government officials are formulating plans to advise against long-haul journeys to certain destinations should tensions in Iran escalate significantly. Nations including Vietnam, Pakistan, Bangladesh, the Philippines, Myanmar and Ethiopia could be impacted, sources told the Times.

Ministers are also poised to emphasise the “positives” of staycations as concerns grow over overseas bookings. Several major European airlines have recently raised the alarm about impending jet fuel shortages in the weeks ahead, pointing to disruption along their primary supply route through the Strait of Hormuz.

According to UKOilWatch, Britain currently holds just 34 days’ worth of jet fuel reserves. Roughly three-quarters of Europe’s jet fuel originates from the Middle East and passes through the Strait of Hormuz off Iran. Heathrow Airport confirmed on Wednesday that it anticipates passenger figures for the remainder of the year will be impacted by Middle Eastern tensions.

Lufthansa Group plans to scrap 20,000 flights over the next six months in an effort to preserve fuel. Meanwhile, other airlines, including Virgin Atlantic, have imposed a fuel surcharge, and British Airways has warned passengers about potential “pricing adjustments” to their tickets.

Sir Keir Starmer, the Prime Minister, also indicated this week that Britons might need to reconsider “where they go on holiday”. Government ministers maintain the UK isn’t currently experiencing jet fuel shortages, as alternative supply sources remain available.

Michael O’Leary, chief executive of Ryanair, Europe’s largest airline, told The Times that rivals are “desperately” searching for flights to cancel, with cancellations expected to commence within weeks.

According to the newspaper, major fuel suppliers are telling airlines that the UK has the “most limited visibility” across Europe regarding jet fuel availability, largely due to its heavy reliance on Middle Eastern imports. These suppliers reportedly anticipate that May will be manageable. Yet they warn that “mid to late June ” is the potential start of disruptions if the Strait of Hormuz near Iran remains closed.

O’Leary explained: “There is a modest improvement in the supply situation through to the end of May, early June, but then nobody would give us any undertakings what happens in mid-June or thereafter.”

He confirmed Ryanair would not be cutting flights. However, he predicted that other major European carriers more “exposed” to spiralling costs would likely start axing routes, saying: “They are all desperately trying to take out marginal flights or any growth because they don’t have the fuel for it.

“We were worried there would be disruption to around 10 per cent of our flights but some of those worries have eased because other European airlines have taken out lots of capacity.” Meanwhile, Jet2 has disclosed that holidaymakers are increasingly opting for last-minute bookings following the outbreak of the Iran war, amid mounting concerns over the conflict’s impact and potential disruptions to jet fuel supplies.

The firm revealed that summer passenger bookings are currently up 6.2%, buoyed by growth across both its airline and package holiday divisions. However, underlining growing unease among travellers, it noted that the “booking profile has become increasingly close to departure” as a direct consequence of the Middle East conflict. Jet2 has confirmed it possesses robust safeguards against fuel cost surges stemming from the Iran conflict during the vital summer season. The airline stated it is “maintaining frequent dialogue with our fuel suppliers and airport partners on fuel supply”.

Meanwhile, British refineries have been ordered to maximise jet fuel output as part of Government emergency planning amid fears that the Iran conflict could result in aircraft being grounded. Energy minister Michael Shanks revealed the Government is closely tracking UK jet fuel reserves and maintaining contact with airlines, airports, fuel providers and international allies.

“UK airlines typically buy fuel months in advance, and aviation fuel suppliers hold bunkered stocks. The UK imports jet fuel supplies from a range of countries not reliant on the strait, including the United States,” Shanks stated in a ministerial announcement. “Airlines UK have stated that ‘UK airlines continue to operate normally and are not experiencing issues with jet fuel supply.’ The government continues to work with partners to monitor and mitigate potential disruptions,” Shanks added.