Concerns about a possible jet fuel shortage linked to the Iran war are unsettling travellers in Germany, according to a survey.

Almost one in five respondents in a representative poll commissioned by expense management company SAP Concur said they had already cancelled or rebooked a flight over the concerns, or had seen an airline cancel their flight.

A clear majority of respondents, 62%, said they had already changed their travel behaviour because of the threat of disruption. Almost half, or 46%, said they were switching to trains or cars, while 39% said they were booking earlier and 31% had postponed travel decisions for now.

Business travellers appear to be less concerned.

Only around one in six business travellers, or 17%, said they had changed their travel plans in this way. So far, cancellations or rebookings have affected only a small share of business travellers, at 6%.

SAP Concur said companies should prepare so they can respond quickly and efficiently to flight cancellations.

“Anyone travelling in the coming weeks should plan flexibly,” said Michael Schmitz, a manager at SAP Concur. “That means considering alternatives to flying, such as trains or rental cars, where possible, and rebooking as quickly as possible in the event of cancellations. Travellers should document any additional costs and keep their receipts.”

German Economy Minister Katherina Reiche announced countermeasures in April in the event of a jet fuel shortage, but warned against undue alarm.

“Alarmism over kerosene does not help,” she said.

Reiche said the supply situation varied from market to market. The International Energy Agency had warned in mid-April that several European countries could start facing jet fuel shortages in June if supplies from the Middle East remain disrupted.