According to the figures, which cover the 'short' tax years of 2001 and 2002, 30 individuals with incomes of more than EUR1 million per year who were resident in Ireland for tax purposes paid only small amounts of tax, and in some cases no tax at all. An additional 67 individuals whose income was between EUR500,000 and EUR1 million paid tax at the 20% marginal rate, while a further 10 people paid no tax.

The data was released by the Irish Revenue Commission at the request of Mr Cowen in response to a parliamentary question by Labour Party finance spokeswoman, Joan Burton.

Mr Cowen explained that the deductions from taxable income include allowances such as capital allowances, losses, allowable expenses and retirement annuities. "In some cases, these will reduce the taxable income to nil," he stated.

The Oireachtas finance committee is currently reviewing a range of tax concessions amid growing calls from opposition members that they are unnecessary and tend to help the wealthy avoid tax. It is also reviewing the rules governing residency for tax purposes. As things stand, persons need to spend more than 183 days in Ireland to be considered resident for tax purposes.

Mrs Burton called upon the review team to address what she views as "fundamental inequalities" in the Irish tax system.

She went on to comment that: "Significant numbers of the ultra well-off are continuing either to pay no tax or low tax despite high incomes. It is an equality issue in the tax system."