Labour wanted nothing less than a complete break between party expenditure and corporate funding, the party leader, Mr Ruairi Quinn, said.

For constitutional reasons, and so as not to disadvantage non-party candidates, Labour did not propose to ban donations made out of the after-tax income of private individuals, he added.

Labour was proposing that a party or candidate should not be permitted to receive any donation except from a registered elector. "In other words, both corporate and overseas donations would be absolutely prohibited."

Mr Quinn was introducing his party's Electoral (Amendment) (Donations to Parties and Candidates) Bill, 2000, in private members' time. The Bill, which will be voted on tonight, proposes:

Restricting political donations to registered electors. A reduction of the threshold above which disclosure of donations must be made, from the existing limits of £4,000 to a party and £500 to an individual, down to £1,000 and £250 respectively.

A limit on the amount which may be donated: £2,000 to a party, including all its candidates, and £1,000 to an individual.

A limit of £2,000 on what can be paid to a political party by way of membership fee by an affiliated organisation.

The removal of the existing prohibition on the spending by political parties of public money at elections.

The provision for an annual statutory audit by the Comptroller and Auditor General of public monies paid to political parties.

Mr Quinn said he believed it acceptable to increase the existing Exchequer subvention as a substitute for funds from private sources.

"While considerable State funding exists, the system effectively compels parties to raise private funds by debarring them from using those public monies at election time."

Given what they now knew from the McCracken report, and from the hearings before the Moriarty and Flood tribunals, he believed it was incumbent on the parties in the House to attempt a restoration of some degree of confidence in the integrity and impartiality of public administration in the State.

"I believe also we should set ourselves a deadline for action which is realistic and achievable. By the time the Dail rises for the summer, all the crucial decisions about what we need to do will have to be taken. Tomorrow night's vote will be one of them."

The Labour spokesman on the environment, Mr Eamon Gilmore, said that even if there were no suggestions of corruption, the time was long overdue to break the financial link between business and politics.

"Contrary to what some commentators would now have us believe, the corporate funding of political parties and political campaigns is not the third secret of Fatima."

The Labour Bill was described as "timely and worthwhile" by the Fine Gael leader, Mr John Bruton, who said his party would be voting for it.

Fine Gael had some reservations about the Bill, but would support its passage through second stage so that it could be teased out in committee. He added that his party had published many complementary proposals to the Bill in its discussion document on the funding of political parties.

Fine Gael would go further than the Bill, said Mr Bruton. Donations to political parties by wealthy individuals, unincorporated businesses, groups lobbying for particular interests or causes, professional partnerships (such as solicitors, accountants, architects), were no different from corporate donations and should hardly be treated differently in legislation.

"If the limits for individuals and companies are set at different levels, companies who want to evade the limits might do so by giving funds to directors to enable them to make donations in an individual capacity.

"A donation by a private landowner is no different from a donation by a building company. More discussion is required on the distinction between corporate and other donations. This is artificial and could be easily evaded."

Fine Gael, Mr Bruton added, believed that any Bill addressing the issue should deal with the following matters:

regulation of the benefits a party might derive from the links with other organisations, which might provide them with political leverage or cross-subsidies in cash or kind.

The sourcing of donations or funding from individuals or companies based outside Ireland.

The funding resources of non-political individuals or groups which campaigned against party candidates or parties.

Mr Bruton said: "Recent allegations call for a comprehensive renewal of Irish politics, putting public service back where it belongs as the touchstone of political action. Legal measures alone, like this Bill, will not be enough to achieve this.

"What is also needed is a moral renewal of Irish politics, reaching back to the standards set by those who founded Irish political democracy in the 1920s and 1930s."

Young people, said Mr Bruton, must see politics as a vocation, as above all a calling to serve the public interest, which made it different from most forms of employment, where the main purpose was to make a living.

"Unless things change, young people will not see Irish politics that way."