British Airways today threw down a challenge to the no-frills carriers by launching a "value calculator" on its website.

Low-fare airlines, such as Ryanair and easyJet, charge for taking hold luggage on flights in an effort to cut down on the basic cost of tickets.

The budget airlines also sometimes charge for check-in facilities and priority boarding.

Today, BA said it was publishing cost comparison details on its website, saying just how much passengers can pay on rival airlines' flights.

BA UK and Ireland sales chief Richard Tams said: "With BA, the price you see is the price you pay.

"It's been well documented that some of the no-frills carriers charge for a range of 'extras' that we consider to be part of our core service, from checking in a bag to food and drinks on board.

"We're just making these transparent for customers.

"On a round trip, customers can be paying up to £375 on Ryanair and £79 on easyJet for these extras in addition to their fare."