Ireland's tax policies could contribute to a loss of revenue in developing countries, according to a new report by Christian Aid.

The research claims that a double tax agreement (DTA) signed with Ghana last year will allow firms there to significantly reduce what they owe in tax by moving money between it and Ireland.

The agreement, which has yet to be approved by the Ghanaian parliament, enables the withholding tax on royalty payments to Ireland to be cut from the domestic rate of 15% to 8%. 

The tax on technical service fees are also being reduced from 20% to 10% under the DTA. 

"Intentionally targeting a developing country to sign a tax treaty flies in the face of findings of the government's own analysis, the advice of the Department of Foreign Affairs and Trade and even the IMF who recommend developing countries not to sign double tax agreements with rich countries," said Sorley McCaughey, Christian Aid Ireland's head of policy and advocacy.

"It is difficult to justify pursuing this damaging treaty when all the evidence suggests it will not in itself promote investment in Ghana but will certainly hurt Ghanaian efforts to raise badly needed taxes," he said. 

The report does not put a specific figure on how much the Irish agreement will - when active - cost the Ghanaian economy, where four million people live in poverty and 5% of children die before their fifth birthday. 

But in general, the study estimates that poorer countries around the world are losing around $416 billion each year as a result of their tax arrangements with more developed states. 

This figure includes $200 billion in corporate tax, $158m in tax lost due to mispricing and $58 billion in untaxed offshore wealth.

Christian Aid claims companies and wealthy individuals are exploiting such loopholes to avoid paying tax and as a result developing countries are in effect "being robbed" of revenues. 

Developed countries and the UN are being urged by the organisation to stop tolerating these flows of money. 

It also calls for the definition set by governments of what constitutes an illicit financial flaw to be widened to beyond illegal actions, to include harmful tax practices that impact on human rights. 

The report, "Trapped in Illicit Finance", is being launched today to coincide with the UN General Assembly in New York which will give consideration to how money needed to end world poverty and hunger can be raised.