Ireland's Naval Service is considering placing a €130m order for two new British-built vessels.
Pressure to sanction the order has been mounting, because the service could save millions on the cost if the order is placed with a UK shipyard.
The euro has been trading strongly against sterling owing to Brexit, meaning the cost of the ship order in real terms has fallen over the space of 12 months.
The Naval Service has expressed satisfaction with a previous €150m three-ship order.
This was completed with the delivery of the €50m LÉ William Butler Yeats last year, which provided Ireland with the youngest navy fleet in the State's history.
A fourth vessel of the same class, to be named LÉ George Bernard Shaw, has been laid down in UK shipyard, Babcock Marine, and is now due for delivery in late 2018.
The ship builder is eager to secure an expanded follow-on order with Ireland.
Ireland's White Paper on Defence outlines a single, larger, multi-role vessel, which would become our flagship should the order with the British company go ahead.
Five Irish ships - LÉ Niamh, LÉ Róisín, LÉ James Joyce, LÉ Samuel Beckett and LÉ William Butler Yeats - have been built to essentially the same offshore patrol vessel design since 1999.
The sixth, LÉ George Bernard Shaw, will enter service in 2019.