Ryanair has announced plans to move its headquarters operation from Dublin Airport to a building in the nearby Airside Business Park in Swords.

It is understood that he 100,000 sq ft building was owned by property developer David Daly.

The acquisition price was not disclosed.

The Swords office will house all of Ryanair's Irish operations.

It plans to move about 400 staff into Airside before the end of 2013 and will shortly tender for the fit-out of the building.

As the office is too big for its needs, Ryanair expects to rent about half of the space to other tenants.

Ryanair said it would maintain "some facilities" at its Dublin Airport base for pilots and cabin crew.

The building is rented from the Dublin Airport Authority and it is understood that the lease has some years to run.

A spokesman for the DAA said "ongoing contractual arrangements" are in place.

Ryanair declined to comment.