Ryanair responded last night at an Aer Lingus promotion for low-price fares to London, the USA and other European destinations, by cutting its own fares on certain routes.

The Aer Lingus promotion from Dublin to Stansted is £49 while the Ryanair one is £39 return. Ryanair also reduced the Aer Lingus Paris and Brussels return fares by £20 to £69. However, both airlines fly into different airports.

Ryanair also knocked £10 off the Cork-London fare which Aer Lingus was offering for £59 return.

Ryanair's commercial director, Mr Tim Jeans, said Ryanair was not surprised at Aer Lingus's move. "Time and time again they say that their `full service' justifies higher fares, and yet just as often they try to beat Ryanair's prices."

Aer Lingus is also offering special fares on several routes on which Ryanair does not compete. These include £89 return fares to Zurich, Copenhagen, Dusseldorf and Frankfurt.

The offers being marketed by both airlines are for a limited period and must be booked this month.