“We are experiencing an enormous demand for tickets right now,” said Ulf Wallin at SJ after the decision to close all Swedish airports except for Visby on Gotland, which is to remain operational until 10pm.

But the rail operator is struggling to find extra carriages and trains as it is still running at reduced capacity following the serious problems that affected rail traffic during the winter.

“Thursdays and Fridays are normally high-pressure travel days so we normally run with all the capacity we have. But we have still managed to get seven or eight extra carriages for the night trains to northern Sweden. And we’re reviewing how we can release more carriages,” Wallin said.

“Saturday is otherwise the calmest day of the week but I am sure that we will also then add more carriages if this pressure on the booking system continues, but it depends on how the cloud develops,” he said.

If planes are cancelled or are more than five hours late then passengers have the right to re-book their tickets or cancel their trips. This applies even to extraordinary events.

“It is up to the individual traveller. If you cancel you get back the full amount,” confirmed Jessie Cargill-Ek, a lawyer at the Swedish Consumer Agency (Konsumentverket).

Anyone re-booking their flight or waiting for a delayed flight and thus forced to remain at the airport has the right to the provision of food and drink in proportion to their waiting time.

“If you are catching a connection or have re-booked then you could have the right to a hotel room if required, as well as transport to and from the hotel. However, if you cancel then you can not expect to get any further help from the airline,” said Jessie Cargill-Ek.

Coach services operator Swebus has also reported increased ticket sales.

“After lunch, our sales started to increase and it seems now to have really gathered pace. We are ready to provide more seats during the day and tomorrow,” said Ingvar Ryggesjö at the firm.

“We are used to dealing with weekend traffic and we have a network of sub-contractors which we use for festivals and Christmas holidays and so on; we therefore have significant capacity to call on. We can bring in extra resources at short notice, within around a few hours, which amounts to about a 50 percent increase,” he said.

Even if the cloud of ash, which has been caused by Wednesday’s eruption under a glacier in the Eyjafjallajökull area of Iceland, were to remain over Sweden for an extended period of time, Ryggesjö is confident that Swebus can meet demand.

“Yes we can, as we did last winter when the trains were left standing still,” said Ryggesjö.