The government has announced it will impose a ban on large trawlers from accessing waters within six nautical miles of the Irish coast.
The ban will apply for vessels over 18 metres in length from January 1, 2020.
It follows a lengthy public consultation on the subject, which ran from April to June this year.
In a statement, Minister for Agriculture, Food and the Marine Michael Creed said the move would benefit smaller vessels who rely on inshore waters as well as the wider ecosystem and nursery areas.
"I am satisfied that there are sufficient fishing opportunities for these vessels outside of six nautical miles," he said.
The Irish Wildlife Trust (IWT) welcomed the news, saying it was " a very significant step towards conservation of the marine environment".
IWT Campaigns Officer, Pádraic Fogarty says “We’d like to thank all the people who made submissions to the Minister to bring this decision about. It will hopefully mark the point where sea life starts to rebound from decades of overfishing. While much more needs to be done this is an important milestone.”