The Minister for the Environment is to finalise legislative proposals later this year that are expected to allow for a substantial increase in corporate donations to political parties.
Opposition parties yesterday accused Mr Cullen of seeking to build up a major election "war chest" in advance of the next general election.
Mr Cullen, who was the biggest recipient of political donations last year, is planning to table several amendments to the Electoral Act that set limits on political spending and donations.
The Minister, in a weekend interview, said he believed the public should not be the ones to fund the political system and that the corporate sector should be encouraged to do so.
He also said he believed limits were needed for individual donations, but he was not convinced of the value of limits to corporate donations.
However, Labour's spokesman on the environment, Mr Eamon Gilmore, said the Minister was seeking to return to a situation where business funded politics without limitations.
"Politics should be about the contents of the ballot box, not the content of a donor's wallet. The legislation will be dismantled because Fianna Fáil is seeking to build up its war chest ahead for the election," Mr Gilmore said.
"This kind of practice has more in common with the US Republican party than any European political party."
Mr Gilmore accepted there were "administrative problems" with the existing legislation, but this could be easily improved without affecting the substance of the Act.
Fine Gael, which accepts corporate donations, also said it would fight any plans to abolish the spending limits in the Dáil.
The party spokesman, Mr Bernard Allen, said: "It is worrying that this move comes from the man who is responsible for planning laws and housing policy, an area which has been fertile ground for dubious practice in the past."
The Green Party's finance spokesman, Mr Dan Boyle, described the move as a "backward step" and said consideration should be given to ending corporation donations entirely.
Under the Electoral Act, political parties can accept donations from one source of up to €6,348 in a given year, while donations to individual politicians are limited to €2,539 per donor.
The cap hit the finances of Fianna Fáil in the general election and the Nice referendums.
Government sources say the limits have meant that people who wanted to make donations to the Nice campaign could not because of the cap.
They also point out that the scale of Irish corporate donations are modest by world standards.
