LONDON , England ( CNN ) -- The ever budget-conscious boss of Ryanair has suggested the discount airline may start charging passengers for using the toilet on board its flights . Whatever you do , do n't drink too much before your flight . Ryanair 's investigating onboard fees for flushing . Michael O'Leary said the airline had revived inquiries into whether the airline could install coin-operated toilets on its fleet . `` People might actually have to spend a pound to spend a penny in future , '' he said in a BBC interview , adding `` We 're always in Ryanair looking at the ways of constantly lowering the costs of air travel and making it more affordable and easier for passengers to fly with us . '' Asked by the incredulous presenter what passengers would do if they found themselves without money mid-flight , O'Leary replied : `` I do n't think there is anybody in history that has got on board a Ryanair aircraft with less than a pound . '' Sound Off : Is it fair to charge a fee for a flush ? The Irish airline is renowned for its cheap flights and regularly advertises competition-crushing deals to boost capacity on its short-haul routes . The company has made no secret of its quest to boost revenue by any means possible . It already charges for food and each bag checked into the hold is subject to a fee . Last week Ryanair announced plans to remove all its check-in counters in an effort to encourage travelers to take just one piece of hand-luggage . Ryanair 's latest revenue-raising proposal has surprised few in the industry who are accustomed to its method of business . `` It seems Ryanair is prepared to plumb any depth to make a fast buck and , once again , is putting profit before the comfort of its customer , '' said Rochelle Turner , Head of Research at Which ? Holiday . The consumer group also warned that move might hit Ryanair where it hurts . `` Charging people to go to the toilet might result in fewer people buying overpriced drinks on board , though -- that would serve Ryanair right , '' Turner said .
Passengers on board these flights may want to take advantage of spare ##s . My boss says he 's considering installing coin - operated machines on fleet . Which ? Holiday , it may encourage passengers to spend less on drinks .