The Transport Minister Shane Ross has described the Road Safety Authority as being "amateurish".

The claim was made in correspondence with the RSA chairperson Liz O'Donnell, that's been published in today's Sunday Independent.

In one email, the Transport Minister also claimed the Authority was "cavalier" in its approach to detail.

In response, Liz O'Donnell said the Minister's comments were "ill-judged and offensive".

The exchange centred on the Minister's decision to reduce the number of directors on the board of the Road Safety Authority.