Easyjet has announced it is to trial allocated seating.

The low-cost airline is to charge £3 for most seats, with extra leg room - which comes with the exit or front row seats -  costing £12. It said the plan was "revenue neutral", however -  it had recently saved money on higher baggage charges and had no need to squeeze customers further.

The new service aims to reduce passenger stress - for some, the scramble for seats raises blood pressure at the start of a flight. Easyjet said surveys showed the prospect of racing for an aisle seat had been putting customers off.

Easyjet was a key player in the low cost flying revolution - and unreserved seating a signature feature. It was seen as a faster way to get passengers from the airport entrance to the air - efficiency being the watchword of this particular business model.

The move may be seen as part of a trend which is blurring the distinction between low cost airlines and their more upmarket competitors.

The company said it would not continue with the trial if it slowed the operation.

EasyJet has said its losses for the half-year would be smaller than expected. As well as benefiting from the extra baggage charges, an introduction on a universal administration fee, rather than a debit card booking fee, has helped. The recent spell of good weather, and the fact that Ryanair reduced its capacity this winter has also benefited Easyjet.