The competition watchdog has said it is concerned that the proposed purchase of mobile network tower firms Cellnex Ireland and Cignal Infrastructure by Phoenix Tower International (PTI) could reduce competition in the sector.
The Competition and Consumer Protection Commission made the comments as it issued its preliminary assessment to both parties involved in the deal.
"The assessment sets out the CCPC's preliminary concerns about how the proposed acquisition could reduce competition in the passive infrastructure sector," the CCPC said.
"Passive infrastructure, which includes towers or masts, is crucial for mobile network operators and other service providers."
"Mobile operators fix active network equipment to it, including antennae and dishes."
The parties have a chance to respond in writing to the assessment before a final determination is made, which the CCPC said would be no later than February of next year.
Oral submissions can also be made the CCPC said, while access can be provided to its file.
"We are committed to investing in the development of robust and advanced telecommunications infrastructure that will benefit both Irish consumers and our valued Mobile Network Operator partners," said PTI.
"We look forward to engaging further with the CCPC as part of their process."
The CCPC opened a full phase two investigation into the proposed deal in July, after a preliminary assessment following its notification in March.
Spanish based Cellnex agreed to sell its Irish mobile tower unit to Phoenix for €971m.
Cellnex currently manages around 1,900 mast sites across the country.
It entered the Irish market five years ago when it bought Cignal.
However, it subsequently increased its footprint in 2022 after it acquired the infrastructure portfolio of CK Hutchinson in six countries, including Ireland.
Cellnex currently manages over 138,000 sites, including planned rollouts over the next six years, across 12 European countries.
Founded in 2013, PTI is based in Florida in the US.
In 2020 it bought 650 towers owned by the eir owned Emerald Tower for a reported €300m.
Customers of independent tower companies in Ireland such Phoenix and Cellnex include the three mobile network operators Three, eir, and Vodafone, as well as fixed wireless access operators, wireless broadband network operators and emergency services.
