The Deputy Secretary General of the OECD has described presumptive US Republican Presidential nominee Donald Trump as a "lunatic" whose political rise mirrors that of Hitler and Mussolini.
Speaking on RTÉ’s This Week, Doug Frantz said rising global inequality had given rise to populist figures like Mr Trump, which he said was "very close to the definition of fascism".
Mr Frantz said: "I’m not suggesting yet that Donald Trump, for instance is a fascist, but if you look at fascist appeal, if you look at the fears that they exploit, if you look at the class divisions they exploit, if you look at the basis ‘us and them’ that Donald Trump sets up, that Hitler set up, that Mussolini set up, then you can begin to at least be concerned and I’m concerned: I think any right-minded person should be concerned".
Mr Frantz also said that the prospect of Mr Trump winning the US Presidency represented "a real threat".
"The person who sits in the White House is the most powerful person in the world and if that person is someone who follows every whim and appeals to the most base instincts of a population, then we’re all under real threat".
Founded in 1966, the Organisation of Economic Co-operation and Development promotes "policies that will improve the economic and social well-being of people around the world".
The organisation’s Base Erosion and Profit Shifting, which targets aggressive tax-avoidance by companies was endorsed by the G20 in February.
Asked what his assessment of Ireland’s tax regime was, Mr Frantz said "I think the responsibility belongs to the US Congress for its repeated failure for decades to reform the corporate tax structure in the United States and also an equal share of the blame goes to greedy multinational enterprises that search for the best tax opportunities available for them.
"I think that the idea that your only responsibility as a CEO is to the shareholders is wrong. I think you have social responsibilities, I think you have responsibilities to your workforce and I think that those responsibilities mean you should pay your own fair share of taxes...We need to make it less palatable for multinational enterprises to engage in these legal tax avoidance measures".
'Panama papers brought shame to country'
Mr Frantz, a former Pulitzer prize-winning investigative journalist and a former employee of the US State Department, said he believed the leaking of the Panama Papers, which exposed the offshore tax arrangements offered by Panama had "shamed" the Central American country.
"The Panama Papers has shamed Panama and rightly so" he said.
"Panama has had a ‘come to Jesus’ moment and we’ve seen them around the OECD lately. They’re looking for a way out of this hall of shame in which they find themselves."
Speaking in Brussels at the European Commission’s European Development Day conference, Mr Frantz also told RTÉ that he believed the controversial €6bn EU-Turkey deal on migration, visas and trade amounted to "extortion".
"I think it’s extortion because Tayyip Erdogan, the President of Turkey has demanded in exchange for this money; in exchange for allowing the EU to outsource its migration problem to Turkey; he’s demanding visa-free access to the EU for Turkey; he’s demanding an acceleration of Turkey’s accession package and this comes at a time when Turkey is moving in completely the other direction in terms of what you want in the European Union, I’m sorry to say".
Mr Frantz the said the president of Turkey, an OECD member had "become a very authoritarian leader".
"Human rights are at risk in Turkey; freedom of expression is disappearing in Turkey; and so you have this very bad political situation in Turkey and yet Europe, because it doesn’t want to develop its own policies and spend this money where it should is outsourcing this problem to Turkey: I think that’s a pretty classic definition of extortion", he said.