The Public Accounts Committee has heard that €5.2m in unpaid M50 tolls were written off last year, with €4.9m written off the previous year.

The matter was raised by the chair of the committee, Fianna Fáil's Sean Fleming, who noted that for every 22 drivers, one was getting off "scot-free".

Nigel O'Neill of Transport Infrastructure Ireland told the committee that there had always been enforcement on the M50 and that 65 cars were seized by the sheriff, while 2,648 judgments were secured as a result of non-payment of tolls.

Mr Fleming said the unpaid tolls amounted to over a million journeys, however Mr O'Neill said this was out of  a total of 50m journeys a year.

Nigel O'Neill of Transport Infrastructure Ireland