The 1.7-billion euro ($2-billion) defence spending plan was announced by Helen McEntee during a visit to the Curragh army camp in County Kildare, west of Dublin.

The plan will include spending on "counter-drone technology" that should be in place by next summer, when Ireland will host the rotating six-month EU presidency.

"That will be there to be able to detect, identify and essentially neutralise any drones that may be a threat," she told reporters.

"We are focusing on the expansion and development of a new radar system" that will be developed by 2028, McEntee added.

Several unidentified drones were seen in the skies when Zelensky's plane landed in Dublin on December 1, with similar sightings over airports and sensitive infrastructure rattling European countries in recent months.

"There was identification of drones in the skies at certain times, there is a review underway at the moment," said McEntee, adding that police and army are investigating the incident.

During a visit to Dublin on Tuesday, European Council President Antonio Costa said the incident "is another example of the hybrid attacks from Russia and the hybrid threats from Russia in the European territory".

At the same joint press conference, Irish prime minister Micheal Martin agreed with Costa, saying that the "drone incident does fit in... with an established pattern of similar disruption incidents that have taken place in other European states".

McEntee told reporters the spending package includes "significant investment in the purchasing of new aircraft and the purchasing of new personnel carriers and fleets".

She also said it would boost investment in expanding "sonar capacity" to monitor seabeds and protect undersea cables, with European countries expressing growing concerns about the risk Moscow poses to critical undersea infrastructure following the suspected sabotage of subsea cables in recent months.