Fair trading officials have clashed with Ryanair over the reason the Irish airline gave for introducing extra charges for its passengers.
Ryanair said it was bringing in a 2% processing fee on all new credit card bookings made from Friday.
The no-frills carrier, which is also scrapping exemptions from its £6 website administration fee, said it was introducing the £2 fee "in order to comply with the UK Office of Fair Trading's (OFT) recent ruling on credit card fees".
But the OFT said: "We have not required any airline to introduce new payment charges, increase their credit card charges or scrap any discounts they wish to offer."
The OFT added: "We took action to make sure that debit card charges are included in the headline price and credit card charges are transparent and not sprung on shoppers towards the end of the booking process."
Those using Ryanair's "cash passport" scheme in Ireland, Germany and Spain will be able to avoid administration fees until February 1, February 15 and March 21 2013 respectively.
Ryanair said it was continuing to "deliver the lowest fares and a no-fuel surcharges guarantee to all our passengers", and that customers could avoid credit card fees by paying with a debit card.
- Your travel plans fall through
<p>If you are a victim of a strike, or any other event beyond the airline's control (including ash clouds!), they must offer you a refund (in which case it's up to you to find a way home) or an alternative flight. While you are waiting for the flight you have the right to food and refreshment and accommodation.</p>
<p>If you are on a package holiday, your tour operator is entirely responsible for looking after you until you get back to the UK.</p>
- Your airline goes bust
<p>This is more likely to happen due to the financial crisis, but in some situations you are covered. </p>
<p>If you pay by credit card and it's over £100, you'll get a refund from the card company. </p>
<p>Your travel insurance may well cover you too, but check before you go. </p>
- Your luggage goes astray
<p>Talk to the airline, and if it is temporarily misplaced they should arrange for it to be sent to your accommodation, and you should be either given cash to cover the essentials in the interim.</p>
<p>If it's completely lost you must wait 21 days and then make a claim for compensation. If you are travelling as part of a package you can claim costs from your operator.</p>
- You get sick
<p>If you are travelling within the EU you need an EHIC card, which gives you access to public healthcare. However, this won't necessarily be free, and if you need extra services such as accommodation for a carer, a helicopter home or a delayed flight, you could end up seriously out of pocket.</p>
<p>The only protection that will guarantee you will be looked after without running up a horrendous debt is by having travel insurance - which often covers up to £10 million of costs.</p>
- You are robbed
<p>The most common form of theft is pick-pocketing, followed by theft from a car and bag snatching. Meanwhile, 752,000 of those surveyed had items stolen from their hotel room or villa.</p>
<p>If you have anything stolen, your only protection is insurance. You need to tell the local police immediately and get a crime reference for your travel insurer.</p>