Political parties in Northern Ireland are to be blocked from major fundraising abroad, the British government announced today.
The plans to close a loophole in the system could deal a huge blow to Sinn Féin's money-making operations in the United States.
British parties are banned from accepting any donations above £200 from donors not based in Britain, but Northern Ireland has remained exempt.
But Northern Ireland minister John Spellar told the House of Commons today that the government does not plan to renew the special arrangements when the order expires next February.
"The Government recognises that the current funding arrangements lack transparency and that they are open to abuse," he said. "Moreover, the current regime creates clear differences between political parties in Northern Ireland on the one hand and those in the rest of the United Kingdom and in Ireland in terms of their access to funds."
The announcement could cause a huge headache for Sinn Féin, which depends heavily on support from Irish-American sympathisers to fund party activities.
Unionist and Conservative politicians have long opposed the different laws operating in Northern Ireland, claiming it gives Republicans an unfair advantage.