Businessman Gerry McCaughey has resigned as chairman of the Dublin Docklands Development Authority.
Mr McCaughey has also stood down as chairman of the Property Registration Authority.
His resignations come after it emerged that he took advantage of a loophole to legally reduce his tax liability when he sold his building company Century Homes in 2005.
Mr McCaughey told RTÉ Radio this was a 'perfectly legal act'.
But he said did not want the country's politicians to become distracted by the issue.
Mr McCaughey also said it would be almost impossible for him to operate as effectively as he would hope as chairman of the DDDA.
He expressed concern about the timing of the news, saying there were sinister forces who wanted to make sure he would not take on the DDDA role.
Mr McCaughey said that like any other businessman selling an asset in Ireland, he got advice about how to reduce his tax liability.
He said that when he got that advice, he stuck to it and had acted perfectly within the law.
He queried why this information had come out now, four weeks after his appointment by Environment Minister John Gormley. He said it was a perfectly legal act and one that he had never tried to hide.
Mr McCaughey's Century Homes was acquired by building materials group Kingspan for €67m in 2005.
