Ms McLeod wrote on the social networking site: “I had previously checked in online but because I hadn't printed out the boarding passes, Ryanair charged me €60 per person! Meaning I had to pay €300 for them to print out a piece of paper! Please ‘like’ if you think that's unfair.” More than 500,000 people lent their support.

But the Ryanair boss branded her “stupid” for falling foul of the airline’s boarding card reissue rules.

“We think Mrs McLeod should pay 60 euros for being so stupid,” he said. “She wasn’t able to print her boarding card because, as you know, there are no internet cafes in Alicante, no hotels where they could print them out for you, and you couldn’t get to a fax machine so some friend at home can print them and fax them to you.

“She wrote to me last week asking for compensation and a gesture of goodwill. To which we have replied, politely but firmly, thank you Mrs McLeod but it was your ****-up.”

He claimed that 99.98 per cent of Ryanair passengers did print their boarding passes in advance: “To those who don't, we say quite politely: ‘B***** off’”.

Although Ms McLeod, 35, from Newbury, printed boarding passes out for herself, her two children, and her parents, on the outgoing flight from Bristol to Alicante, she says she was unable to print out the boarding passes for her return flight due to the length of her holiday. Ryanair only permits passes to be printed out two weeks in advance of departure, but her trip lasted 15 days.

Had Ms McLeod forgotten to print her own boarding passes on the flight from Bristol to Alicante, she would have faced an even greater bill of £300. This is because Ryanair uses an exchange rate of £1=€1 when calculating its numerous fees – a policy which, due to the weak euro, means British passengers are charged more.

The no-frills airline has been criticised in the past for imposing hefty charges on its passengers. In addition to the £60/€60 fee for reissuing boarding passes, passengers are charged a £6/€6 per person per flight “admin fee” and a £6/€6 “web check-in fee”. Ryanair also recently introduced an “EU261 levy” to offset the cost of paying compensation for flight delays and cancellations, and since January it has also charged an “ETS levy” to cover the cost of the EU’s Emissions Trading Scheme, under which airlines are fined for exceeding carbon emissions limits.

Ryanair passengers wishing to check in a single bag, meanwhile, are charged between £15/€15 and £40/€40 per person per flight, depending on the time of year, their destination, and the weight of their luggage. Carriage of sports or musical equipment costs £50/€50.