Taoiseach Micheál Martin has said drones identified over Dublin Bay during Ukrainian President Volodymyr Zelensky's visit are "suggestive of being part of an ongoing Russian inspired hybrid campaign against European and Ukrainian interests".
"It is a very concerning incident," he said.
He was answering questions about national security in the Dáil.
Mr Martin said "right now in this era" there is a "Russian threat to security and security infrastructure".
"A pattern has developed in the emergence of these drones, in terms of violating the airspace of EU member states," he said.
He said while Mr Zelensky's visit was "very effective" from a security perspective, "an incident did occur on that night".
"A small number of unidentified drones were observed in the vicinity of a naval service vessel on patrol off the coast of Dublin," he said.
Response 'appropriate to circumstances' was applied
Mr Martin said an operational response was put in place that was "appropriate to the circumstances" by the commander of the naval vessel, by gardaí and military services.
He said the drones were not a threat to Mr Zelensky's aircraft as it had landed "quite some time prior to this incident".
"They were not a threat either to his departure," he added.
Mr Martin said he has received a report on the drone incident but that some of it is "security sensitive".
He said there are limits on what can be put into the public domain.
The Garda Special Detective Unit is carrying out an investigation of the circumstances of the incident with input from the Defence Forces, he said.
In response to a question from Sinn Féin TD Rose Conway Walsh, Mr Martin said no EU member state, except for France "in the last 48 maybe hours" has "attempted to disable drones" or "bring them down".
This has been for "different reasons", he said.
However, Mr Martin said: "We do have the capacity."
Mr Martin said the Government is "committed" to the delivery of a national security strategy.
"Work is ongoing to finalise the strategy," he said.
He said the Programme for Government acknowledged that "this is a time of upheaval" with threats and challenges arising from a "rapidly changing global geopolitical landscape".
He said the draft strategy focuses on the State's internal security covering a broad range of issues including the dangers of "terrorism, extremism and cyberthreats".
It also has a focus on the need to increase investment on security and to "modernise our legislation in the security field, notably in the investigatory powers ".
Mr Martin said: "It will include also the implications of recent security, defence and international developments and the related impacts."
He said Europe's security system is "deteriorating" due to Russia's war in Ukraine and the "growth in cyber and hybrid threats".
Mr Martin said the strategy will ensure protection for "critical maritime infrastructure, especially critical undersea infrastructure".
Drone sightings 'underline and underscore scale of vulnerabilities'
Fianna Fáil TD Tom Brabazon told the Taoiseach that the recent drone sightings over Dublin Bay "underline and underscore" the "scale of our vulnerabilities".
He said it shows "the urgency and the need for for preparing a strategic national security package".
He said there are reports that international anti-drone units were deployed to Dublin during the visit to assist emergency response unit.
"While we welcome the assistance of other states, we should not have to rely on others for our own defence," he said. "We should be self-reliant."
He said it is expected that this activity will continue when Ireland takes over the EU Presidency next year.
Concerns ahead of EU Presidency
Fianna Fáil TD Ryan O'Meara said during the EU Presidency "our national security will be of paramount importance", also raising the threat of drones.
"It is one thing for us to be a militarily neutral country, but it is another thing to say whether or not we can patrol our own skies and protect our own airspace".
In terms of self-reliance, Mr Martin said Ireland will be developing radar capacity and "that's very close to action".
"We need to cooperate and coordinate with other member states in the European Union and indeed with the United Kingdom," he added.
"These are the realities that we are facing," added Mr Martin.
"We wish we weren't facing these realities. And we would prefer a continent at peace."
