A British company has said it is fast-tracking exploration efforts to access an estimated two trillion cubic feet (TCF) of gas at a site off the west coast.
If successful, that volume of reserves would be around double what is thought to be in the Corrib Gas field, a short distance away.
Europa Oil and Gas said it believes it can access reserves at three locations off the Mayo coast.
It says that it hopes to be in a position to drill an exploration well by late 2019 or in 2020, subject to Government approval.
The company says it would hope to use the infrastructure already in place to process gas from the Corrib field, if its efforts are successful.
This would entail extending the intended lifetime of the Bellanaboy gas terminal in north Mayo.
In an update to investors, Europa said the field, some 16km north west of the Corrib Gas reserves, is in shallow waters, making it much easier and cheaper to access.
The firm's CEO Hugh Mackay cited the existing infrastructure in the region, along with the reduction in output from Corrib in the coming years, are good reasons to fast-track Europa's ambitions.
The company says successful drilling would enhance Ireland's energy security and that it would expect to capture around 80% of the available resources.
It puts the price of exploratory work at around $28m.
Europa says it is reprocessing initial seismic data from 2002 to identify "drillable prospects". It has renamed the area as the Inishkea prospect. The Licensing Option (LO) 16/20 covers an area of 925 km2 in the Slyne Basin.
The company has started to actively seek business partners and says it is confident that it can deliver gas from the field.
In the notification to investors, the company says it is working with a number of people who were involved in the initial discovery of gas by Enterprise Oil in 1996.
At present, supplies from the Corrib field provide around 60% of our daily gas demand. This will peak in the coming years and then fall back from around 2025.
Europa says it believes it could be in a position for supply a significant percentage of future needs for electricity generation or for domestic supply.
The company was given a three year licensing option in 2016. This means that if successful, it would be liable to pay a minimum tax rate of 5% for every year that it had gas wells in commercial production.
The decision to process gas from the Corrib field at an onshore terminal in Bellanaboy caused years of protests in north Mayo. The project was mired in legal disputes, protests and demonstrations. It was eventually completed, almost fifteen years after it was initially scheduled at a total cost of around €3.8bn.
First gas flowed at the end of 2015.
Last year, Shell announced it intended to sell its interest in the Corrib project. The company says it is on schedule to complete that deal by the end of the second quarter of 2018.