The Land Development Agency (LDA) has bought 13.2 hectares of land in north Dublin with the potential to deliver over 2,300 affordable and social homes.
The lands at Clongriffin already have existing planning permission for 1,800 units and if the go-ahead is given for the additional homes, it will be the biggest single State housing project in decades.
The property was bought from the National Asset Management Agency (NAMA) for €44m.
The lands are known as Project Capital North and Barina and amount to a total of 13.2-hectares - 11.1 and 2.1-hectares respectively.
Project Capital North is the site which already carries planning permission for 1,823 units and some commercial developments.
"This is a significant strategic purchase by the LDA and a major development for the provision of State-owned affordable housing," said John Coleman, CEO of the LDA.
"These lands are superbly located and well-connected with the potential to ultimately deliver about 2,300 affordable and social homes. The purchase has involved an upfront financial cost to the LDA of around €19,000 per home, which is low in comparison to the overall delivery cost."
The site is located next to Clongriffin railway station in Dublin 13 and is zoned for housing.
News of the purchase was welcomed by Minister for Housing, Local Government and Heritage Darragh O'Brien.
"The land at Clongriffin is superbly located and it is exciting that this will be the largest State housing project in decades," he said.
"By buying this site, the LDA is realising the land’s potential and making sure it is used to deliver the right type of housing, community facilities and amenities."
Sinn Féin Housing spokesperson Eoin Ó Brion said he welcomed the purchase of the land.
However, he said: "To date, the Land Development Agency have been very slow in their delivery of their pipeline and in increasingly the homes aren't affordable for ordinary working people.
"If this land is to have an impact, the Minister needs to ensure the homes are delivered in a timely manner and crucially that there are prices, whether to rent of buy, that working people can actually afford."
The first accommodation is expected to be delivered on the site by 2026 and Sinn Féin said the Government must work to ensure that the homes are delivered.
Mr Ó Brion said there were also plenty of other sites where local authorities and the LDA could develop social and affordable homes much more quickly
"The problem is there is far too much red tape and bureaucracy imposed by central government on those," he added.