Anyone travelling on an Intercity train over Christmas will have to pre-book their ticket in advance.

The rule will come into force when restrictions on intercounty travel are lifted on December 18th.

It will remain in force until January 6th.

Iarnród Éireann said the pre-booking system will ensure that train capacity can be safely managed.

Trains will run at 50% capacity throughout the period, ensuring passengers can enjoy a “safe and sanitary travelling environment over the Christmas and New Year period.”

The train service asked customers to only travel if their journey is necessary and to avoid peak and busier times where possible.

Passengers existing tickets, including open returns, season tickets and Department of Social Protection travel passes still need to book their seat.

Intercity travel can be pre-booked at irishrail.ie.