The Oireachtas should have greater powers to inspect the Minister for Finance's budget preparations, the Dáil's Public Accounts Committee (PAC) has demanded.
The existing budget rules, which separate spending and taxation announcements, should be scrapped, the spending watchdog recommended.
Negotiations between the Minister for Finance and his Cabinet colleagues should start in January and end by the summer, rather than stretching into November as they do now.
The budget should be published in September when TDs resume after the summer break, and it should then be examined for months by the Dáil's Finance and Public Service committee.
TDs, said the Labour leader, Pat Rabbitte, currently pass departments' budgets in just a few hours because they have no power to force change.
The PAC report proposing alterations to budget rules was written by the Labour leader, though the full PAC examined practices in the United States at state and federal level.
"If implemented, the changes would be very significant. There has been a gradual erosion of the power of parliament over the last 20 years," said Mr Rabbitte.
The Oireachtas should be able to hire expert staff, led by an official with powers to demand papers from the Department of Finance before money is spent.
Comptroller and Auditor General John Purcell has the power to seek papers after money has been spent.
However, the changes would not mean that the Minister for Finance's powers would be cut, Mr Rabbitte told The Irish Times. "It wouldn't mean a cut . . . it would make the Minister and the budget more accountable, more transparent and subject to parliamentary oversight in a way that he isn't now," he said.
TDs would properly inspect spending figures if they were given some influence. "Now they skip over them because they know they can't change them."
Meanwhile, the Comptroller and Auditor General should be given full powers to investigate local government spending.
Under present rules, he may only inspect, not audit, accounts of local authorities in cases where most of the money came from central government.
"The restriction on the comptroller's capacity to account for the expenditure of these sums might not be of concern if local audit was an adequate substitute," said Mr Rabbitte in his 155-page report.
He added: "What is of concern is the lack of any coherent, systematic or sustained response by local authority members to the statements and reports of that service. Put simply and starkly, I am not convinced that local authority audit committees function in any meaningful sense, as a means of ensuring accountability for the stewardship of public funds."
The new rules, if implemented, would not have prevented the Government from announcing its Transport 21 10-year programme in the way that it did.
However, a strengthened Finance and Public Service committee would be able to call for back-up research papers, while the Oireachtas Committee on Transport would be able to start an investigation of its merits before any money was spent.