The government in the Irish Republic has lifted its cap on the size of retail outlets, paving the way for Ikea to enter the Irish market.
Ikea wants to open a 28,000 sq metre warehouse
The Swedish furniture giant threatened to set up in Northern Ireland if planning restrictions were not relaxed for a proposed site in north Dublin.
The new rules will apply to four areas of Dublin.
They will also apply to towns designated as "gateways" under the National Spatial Strategy.
Irish environment minister Dick Roche said the changes were made to benefit consumers not any one business group.
He said: "I made these changes because I believe that it is a very vibrant consumer market here.
"I believe that consumers require the kind of choice that consumers have elsewhere."
The planned 28,000 square metres Ikea outlet at Ballymun would be more than four times the limit for a retail development.
There have also been fears that it could lead to traffic problems on the nearby M50 motorway.
Ikea claimed the outlet would create 500 jobs.