Michael O’Leary has said that Ireland should threaten to leave the EU if the European Commission ruling ordering Apple to pay up to €13 billion in back taxes is upheld.
In an interview on Newstalk Breakfast, the Ryanair CEO urged the government to demand that the decision is reversed.
"They should go into commission and ministerial meetings, hit the table and say: 'We’re not tolerating this. If this isn’t withdrawn, we’ll consider leaving the EU.'
"That’ll soften their cough," he said.
Mr O’Leary added that he was "disturbed" by Ireland’s "limp-wristed" response to the ruling.
"One of the key fundamental tenets of the European Union is tax autonomy… and Ireland should defend that to the hilt. We should not be told 10 years after the event by some Danish state aid commissioner: 'Sorry, we don’t like the way you don’t that.'
"They only do it to the small countries… This is a case of the European Commission bullying Ireland and Ireland should respond with a far more robust response than just appealing the decision."
The businessman also weighed in on the current Dublin Bus dispute, accusing workers of holding the public "to ransom" ahead of another 48-hour strike.
The Ryanair boss said the "entirely mismanaged" company should be privatised.
No Dublin Bus routes will operate on Thursday or Friday due to industrial action by SIPTU and NBRU.
The drivers are seeking a 15% wage increase over three years, as well as a pavement in lieu of an agreed 6% hike that was deferred in 2009.
"This is a company that loses about €50 million a year and receives a public subsidy of €50-60 million a year so they can report what they call a surplus," Mr O’Leary said.
"If you privatise them, I think you can provide all those services at a far lower rate and at much lower prices.
"If you look at most UK cities, bus services were privatised many years ago.
"They’ve been run by coach, they don’t have strikes and bus fares are fractions of the relatively high fares charged in Dublin."
Michael O'Leary accuses Dublin Bus drivers of holding public 'to ransom': https://t.co/FhWgj6ODrf pic.twitter.com/z1owLGKfJh
— Newstalk (@NewstalkFM) September 14, 2016
'Red rag to a bull'
The businessman also said that private company should be allowed to take over services in the event of transport stoppages.
"Why don’t we allow private operators like Swords Express to run bus services into the centre of town?
"I don’t understand what the Department of Transport actually does other than sit on its hands when there’s a bus strike.
"If it’s a red rag to a bull, fine, but the bulls need to understand that if you want to go on strike and hold the public to ransom, which is what they’re doing, we have alternatives."
However, he said he thought Minister for Transport Shane Ross' instincts were "in the right place" judging by his past writings.
"I think he's handling the bus strike in the right way: stay out of it because it's nothing to do with a government minister."
Mr O'Leary told the programme that Ryanair remains on track to post profits of €1.4 billion for the financial year ending in March.
"It's a difficult environment out there and if there are any unforeseen events - like terrorism - that earnings guidance may need to be revised," he added.
He also spoke about his concerns for the British economy as uncertainty over the Brexit referendum continues.
"The growth prospects for the UK in Europe have certainly taken a dip for the next number of years... I struggle to see how UK can leave the single market, in which case they’ll have to concede free movement of people.
"I think Brexiteers will have achieved very little. Personally, I believe they were misled during the election."
