Ireland has an 'additional responsibility' by choosing not to join any military alliance, Taoiseach Leo Varadkar has said.
He was speaking after the Government's Forum on International Security Policy met in Cork earlier.
Protesters interrupted a speech by Tánaiste Micheál Martin, shouting ‘shame on you’ and ‘you’re a disgrace’ as well as ‘no to NATO, no to war’.
Mr Varadkar told The Hard Shoulder we need to focus on our own defences.
"We're not going to join NATO, both the Tánaiste and I made that very clear," he said.
"From my point of view... I believe we need to increase our own defence capabilities.
"We're an island, we've a lot of air above us and a lot of seas - much greater seas in our Exclusive Economic Zone than we have territory.
"So we need to increase our own defence capability, first and foremost - but also I think it's the right thing to cooperate with like-minded countries".
'Binary' idea of neutrality
Mr Varadkar said Ireland is not a neutral country.
"This kind of idea of neutrality or not neutrality is overly binary in my view," he said.
"Ireland has never been politically neutral, even during the Second World War when de Valera first announced the policy of neutrality we helped the allies and we were on the side of the allies.
"We did not want Nazi Germany to win.
"Then during the Cold War... we were on the side of western democracy and freedom, and we joined the European Union.
"It's never been the case that we're somehow politically neutral.
"We're not neutral in the war in Ukraine - we're on the side of the people of Ukraine.
"What we've decided as a country, though, is that we're not going to join a military alliance or sign up to a mutual defence clause.
"That actually creates an additional responsibility on us, to make sure that we are better equipped to defend ourselves and doesn't preclude us from cooperating with other countries".
'No aircraft carriers or fighter jets'
Mr Varadkar said defence investments will not be made in things like fighter jets.
"I think a lot of the investments are going to be in things like primary radar... so that we can watch our own skies," he said.
"Things like cyber security, for example... we don't have any plans to buy any aircraft carriers or fighter jets.
"I think for us to do that would be enormously expensive, and we might have five or six of them and it actually wouldn't make a huge difference in terms of our defence.
"That's why cooperation actually is important, and cooperating with allies like the UK, the US and of course in the European Union," he added.
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