Wall Street hedge funds are thought to be leading the campaign to "short sell" Irish government bonds, making vast profits in the process.
US hedge funds Groveland Capital and Corrientes Advisors are thought to have taken major positions against Irish debt. Giant €60bn asset-manager Pictet also revealed that it had earlier bet against Irish government bonds. JP Morgan is also thought to have taken a bearish position on Irish debt.
The International Monetary Fund estimated that up to €3bn of Ireland's debt was being targeted by speculators through the uses of derivatives.
This practice is likely to have increased in recent weeks over growing fears that Ireland may default on some of the Anglo debts.