More than 300,000 homes in broadband blackspots are to get fibre broadband in a plan which looks set to save the taxpayer up to €100m.
The broadband move is set to be announced by Eircom, which will unveil an expansion to its rural broadband plans today.
The communities to be connected are concentrated in rural areas of Cork, Kerry, Galway and Mayo, with rural parts of Clare and Tipperary also due to get the new fibre.
The additional 300,000 homes will be in remote areas that were previously scheduled for the State-subsidised National Broadband Plan. The Government had previously estimated a taxpayer bill of up to €500m for the scheme, which targets 760,000 rural homes and businesses that cannot get access to reasonable broadband.
But Eircom's announcement will take 40pc of this number out of the Government's State-subsidised obligation.
Eircom's move marks a new escalation in the broadband race currently underway between Eircom, UPC and Siro, the joint fibre venture between Vodafone and the ESB.
Last month, Siro unveiled its own alternative fibre broadband network set to roll out to 500,000 Irish homes and businesses over the next three years.
"This marks a significant extra investment by Eircom, to the order of over €300m," said Richard Moat, Eircom chief executive. "It will bring to €700m the total investment in our fibre broadband roll-out over the next five years and shows the willingness of investors to invest in our future products."
The new broadband will be fibre directly to the home, as opposed to existing phone lines that connect to a fibre cabinet some distance from the house. It will deliver broadband speeds of up to 1,000Mbs, four times faster than speeds in Irish cities.
The move means that Eircom's overall high-speed broadband network, including fibre and fibre-connected phone lines, will increase from 1.6 million to 1.9 million premises around the country.
Of this, the company says that 800,000 premises will be get fibre directly into their homes.
The Government is set to launch a tender to cover the remaining 460,000 premises by the end of the year.