Open-access broadband provider SIRO has announced its withdrawal from the Government's National Broadband Plan tender process.
In a statement SIRO, which is a joint venture between the ESB and Vodafone, said it "cannot develop a competitive business case to justify continued participation" in the tender process.
The National Broadband Plan initially aimed to connect around 842,000 homes and businessess to high-speed broadband.
Three companies - Eir, SIRO and enet - had been shortlisted for the final phase of the tender process.
Eir confirmed it had submitted a detailed submission for the next stage of the tender process ahead of today's 12pm deadline.
Enet also confirmed its continued involvement in the process, while adding that electricity provider SSE has joined its consortium.
SIRO's decision to withdraw follows a deal agreed between the Government and Eir in April that is set to see 300,000 premises in rural areas around the country removed from the National Broadband Plan.
Instead, Eir said it would connect these homes and businesses to high-speed broadband by the end of next year.
This leaves the number of premises to be connected via the plan at around 542,000.
At the time of the agreement sources suggested the removal of 300,000 premises from the tender, many of which may have cost less to connect to a high speed network due to their location compared to more remote properties, would make the State contracts less attractive for the bidders.
SIRO CEO Sean Atkinson said the decision to withdraw from the National Broadband Plan tender was "not been taken lightly".
He added: "We will continue with our original plans focusing on transforming Ireland's regional towns, putting them on a par for high speed connectivity with cities like Tokyo and Hong Kong.
"SIRO's Gigabit towns will attract investment and job-creation, support SMEs and allow access to new services in education, healthcare and entertainment."