Tánaiste and Minister for Defence Micheál Martin has said that Ireland "is not relying on anybody to patrol our airspace".
Mr Martin said media reports this week that there is a long-standing air defence arrangement with the British government were "inaccurate in terms of interdiction", but did not go further, adding that there were "national security issues".
He said that there "may have been occasions in the past" when RAF aircraft have been in Irish airspace "for different reasons".
Mr Martin said that there was no question that there were limitations on Ireland's military capacity and that the Government’s focus was on improving that over time.
He was answering questions from journalists regarding Ireland’s military capabilities ahead of the PDFORRA conference today.
The minister said that Ireland was aware of its "deficiencies", and that "we don’t have sufficient radar right now".
He said the Government had committed to enhancing its capabilities as recommended by the Commission on the Defence Forces report last year and had taken decisions to "significantly increase investment in capital" in the Defence Forces.
"We’ve made a commitment to get to Level 2 ambition as detailed in that report and that’s what we are doing. We are investing in that now, and the focus is on the procurement now of radar and all the necessary ships and capacity on the equipment side," he said.
However, the Tánaiste said it would take "a number of years" for that to happen.
"We don't have a specific time frame, that is now subject to procurement. We know we have quite a lot of procurement underway already in respect of vessels and also in terms of aircraft capability," he said.
"We’ve already ordered and we’ve already entered contracts in respect of some military aircraft but that takes time in terms of the building and procurement of all that."
In relation to the presence of Russian vessels in Irish waters, the Tánaiste said that Ireland has "full capacity to identify where ships are" and that is monitored.
He said people need to be careful about the "sorts of assertions and the general noise" when a few Russian ships appear within our economic zone.
He said it was "not news that they are being monitored, not just by us but by others".
When asked about Ireland being described as "the weakest link" in Europe, Mr Martin said he was "impatient with that kind of language".
He said it was not as if the rest of Europe was depending on Ireland for security.
"I would much prefer a more calmer debate with a degree of perspective, understanding and acknowledging our limitations," he said.
'A very good and effective air corps'
Meanwhile, Taoiseach Leo Varadkar told the Dáil that any air defence arrangements Ireland has "are consistent with our foreign, defence and security policy".
While "we have a very good and effective air corps", Mr Varadkar said that Ireland does "not have an airforce of the nature of the UK or France or Russia or the US. We never will".
"We do have to put in arrangements for certain scenarios," he added, "and we have arrangements for certain scenarios to ensure our safety and national security."
Mr Varadkar noted that he is limited in what he can say on national security.
He was responding to Sinn Féin TD Matt Carthy who said that relying on another country to ensure the safety of our skies "simply isn't good enough".
Mr Carthy said that the agreement is "a scandalous exposure of the failure of successive governments", adding that it was never given a "Dáil debate, never mind Dáil approval".
