The late delivery of new Boeing aircraft has forced Ryanair to scale back its schedule for the first three months of 2006.

Ryanair expects its traffic to be cut by 100,000 passengers per month in January, February and March.

The airline will be forced to retire several Boeing 737-200s within days, but replacement aircraft will not be ready in time.

"These schedule changes will not affect Ryanair's profit guidance for the fiscal year ended March 31st, 2006," deputy chief executive Michael Cawley said.

The company's shares dipped slightly in the morning, but recovered in the evening to close nine cent higher at €7.90.

A Ryanair statement said: "As a result of a strike in Boeing during September and October, all of Ryanair's aircraft deliveries this winter are being delivered approximately one month after their scheduled date."

Ryanair has been able to meet this shortfall during October, November and December by extending the flying programme on a number of older 737-200 series aircraft due for retirement.

However, it is not possible to extend the use of these aircraft beyond the end of December 2005 as they have been sold.

The airline now expects to return to its normal schedule in April.

The airline said the late delivery dates would have three main implications:

the cancellation of 200 rotations per month during January, February and March.

the delay of the launch of a second aircraft at its Nottingham East Midlands base;

a delay of the launch of the second aircraft at its Pisa base.

Passengers affected by cancelled flights will be offered alternative flights or full fare refunds, said a statement.

John Mattimoe, analyst with Merrion Stockbrokers, said he did not envisage the cut in capacity hitting profits.

He said the capacity was likely to come from less profitable routes. Higher average fares across the network would also help.

He welcomed the announcement that Boeing deliveries would be back to normal by April.

The two manufacturers, Airbus and Boeing, are currently locked in fierce competition to win orders from the world's main airlines.