The criticisms, endorsed by all of the main accountancy bodies, follows the frustration endured by thousands of PAYE taxpayers earlier in the year, who experienced long delays in receiving tax credits for 2006, frequent mistakes when the credits eventually arrived, and jammed phone lines when they sought to have the errors rectified.

In a hard-hitting discussion paper, the Consultative Committee of Accountancy Bodies says that the Revenue has been able to freeze staff numbers, despite a four-fold increase in tax revenues over the past 15 years, by shifting the burden of work to the taxpayer. Under self-assessment, it is up to taxpayers to know when they have a liability, calculate the tax due and pay it on time.

But the accountants accuse the Revenue of abusing the system by imposing unrealistic deadlines. "One of the downsides of self-assessment for taxpayers and their agents is that it has permitted Revenue to introduce limits, restrictions and deadlines which would never have been countenanced if Revenue were still fully responsible for the assessment of tax, " according to the accountants.

"No bureaucracy could administer the complexities accountants and taxpayers now undertake as routine matters."

The discussion paper makes 15 recommendations for improving the service given to taxpayers. It suggests the Revenue should publicise its phone usage policies so that taxpayers would know when their calls would be answered, how long they would be left on hold, and when to expect an answering machine.

The accountants also want the Revenue to stop adding new rules until existing backlogs are cleared. "New compliance obligations are unhelpful in attempting to address customer service difficulties which derive from existing compliance obligations, " they state. "Continuing customer service difficulties are undermining taxpayer confidence in the administration of the system overall."

Immigrants are another victim of Revenue foot-dragging, according to the accountants, who claim that workers coming from abroad face long delays in getting their tax affairs in order. "It is a source of puzzlement to taxpayers newly arrived in the country that the process of obtaining PPS and VAT numbers should be so protracted and cumbersome, " they state.

The accountants also believe that their clients should be fast-tracked by the Revenue at the expense of tax-payers who do not engage a tax professional to handle their affairs. "It is now a commercial reality that accounting firms must, if only by virtue of the money-laundering regulations, perform considerable due diligence on new clients to satisfy themselves that they are happy to accept the client's work, " they state.

"It is wasteful and inefficient for this due diligence process to be disregarded when processing applications for tax registration."

Time is also wasted when the Revenue looks for information that taxpayers have already supplied, either directly or to another arm of the state.