Fewer than half of the estimated 420 Esat Digifone masts due to be located at Garda stations throughout the State have been erected to date.
The company said yesterday that about 200 such masts have been erected, and the remainder are scheduled to be in place within two years.
The agreement, reached in November 1996 and finalised early the following year, requires Esat to build the masts or provide necessary replacements at an estimated cost of £37 million. Once erected, the structures would become the property of the State but would be used by both parties for telecommunications.
While Esat has not said exactly how many masts it plans to erect under its development plan, the Garda masts are believed to constitute the majority and are seen as vital for extending the network into rural areas.
The mobile phone company had hoped the deal would enable it to overcome planning difficulties which have disrupted the expansion of its services. But planning applications have been delayed at a number of locations because of strong local opposition.
Among the sites where objections have been made are Collooney, Co Sligo; Clogheen, Co Tipperary; Maam Valley, Co Galway; Multyfarnham, Co Westmeath; Mullaghmore, Co Leitrim; and three towns in Co Cavan.
In Geashill, Co Offaly, last month the entrance to the local Garda station was barricaded by the wife of a garda campaigning against the erection of one of the masts.
Mr Barry Maloney, the company's chief executive, said that opposition was the exception rather than the rule. "By and large, it has been very smooth from everybody's point of view. With most masts, we've been in and out and have had it up within a day."
He said he was surprised that a number of people objecting to the masts were "exactly the same people who are complaining about jobs being lost in their area". But "you can't possibly talk about promoting commerce or technology industries where you don't even have a basic telecommunications network."
Gardai in rural areas had indicated that better mobile phone coverage would assist their operations, particularly in search-and-rescue incidents, he said.
The contract was negotiated between Esat and the Garda by the deputy leader of Fine Gael, Mrs Nora Owen, when she was minister for justice. It was seen as a cost-effective way of creating a secure, digital telecommunications network which would link to the Garda's new £26 million computer system.
Previously, gardai used analogue facilities which were susceptible to interception.
Under the deal, Esat agreed to pay a lease - worth an estimated £3£3.5 million a year for five years to the Garda - for the use of the new radio masts. It also agreed to provide mobile phones and free use of the network to senior Garda personnel.
Esat's market rival, Eircell, objected to being excluded from the deal, leading the Tanaiste and Minister for Enterprise, Trade and Employment to refer the issue to the Competition Authority. The authority said there was no basis in competition law for setting aside the agreement and rejected Eircell's proposal to be given equal access to every Garda site.
As for the safety of the masts, scientific opinions differ. Until recently there was a consensus among scientists that such technology posed no health risk to the public.
But a number of studies over the past two years have suggested there is a risk from telecommunications masts, although most show it is lower than that from using a mobile phone.
An Australian study last year found the incidence of tumour growth doubled in mice after extensive exposure to the type of electromagnetic fields emitted by mobile phones.
The International Commission on Non-Ionising Radiation Protection, whose standards Ireland adopts, has said there is no proof of adverse effects on human beings.
The director of telecommunications regulations, Ms Etain Doyle, completed a study last September of masts owned by RTE, MMDS operators, Eircell and Esat, concluding there was no serious health risk associated with living near the structures.
The study showed that maximum exposure levels of non-ionising radiation at mast sites were at least 1,000 times below guideline limits.