Sinn Fein's US fund-raising wing collected $2.484 million between October 1995 and August 1999.
The figures supplied by Friends of Sinn Fein make the party the biggest recipient of US funding in Ireland. Estimates by its fund-raisers suggest it has raised at least a further $1.5 million since the 1999 returns, taking its earnings since October 1995 to over $4 million. Official returns have yet to be made in the US or in Ireland for this period.
Although the party made declarations of $2,484,804 with the Department of Justice in the United States, the amount recorded with the Public Office Commission in Dublin for the same period is significantly less.
The party's president, Mr Gerry Adams, said yesterday the party received about £100,000 a year from foreign donations. Sinn Fein's declared donations for 1997-1999 under the 1997 Electoral Act are $496,323.
On Sunday Mr Adams objected to Government proposals to control funding by foreign agencies. He said such proposals were "entirely at odds with the all-Ireland dimension of the Good Friday agreement".
The Taoiseach, Mr Ahern, said the playing pitch between participants in the Irish political system should not be distorted by disproportionate sums from overseas.
He said the Government would bring forward amendments to the Prevention of Corruption Bill, 2000, to provide a statutory basis for the prevention, prosecution and punishment of corruption.
There will also be legislation to protect people who disclose corruption in the public interest. And there will be a regulation and registration system for paid political lobbyists.
In recent years Sinn Fein has far outstripped all other Irish political parties in US fund-raising.
According to the returns to the Public Office Commission, Fianna Fail received $10,000 in 1997. Sinn Fein received $122,933 in 1997, $184,256 in 1998 and $117,184 in 1999, a total of $424,373.