The French-Dutch carrier says all passengers whose flights are cancelled amid the pandemic are eligible for refunds, regardless of the date.
O'Leary believes allowing member states to bail out airlines with which it has strong historic links is discriminatory and gives them an unfair advantage over airlines who have not asked for help.
A majority of member states are lobbying to suspend a rule that forces airlines to offer a full refund for cancelled flights. Margrethe Vestager, the EU's Competition czar, warned on Thursday that "some people may need the money".
One social enterprise has been salvaging food to support the most vulnerable people amid the COVID-19 pandemic.
The decision comes at the end of an almost decade-long battle between budget carrier Ryanair and the Italian Competition and Market Authority
While passengers are seeking compensation for cancelled travel, transportation companies are seeking financial help to deal with the economic fallout of coronavirus.
The UK government has pledged £75m (€84m) to help airlines with special charter flights to repatriate tens of thousands of UK nationals.