Northern Ireland motorists travelling in the Republic face a string of new motorway tolls under a plan drawn up for the Dublin government.
The new charges would bring hundreds of thousands of drivers into the tolling 'net' for the first time.
They are part of a raft of measures being recommended to the Republic's government by the National Roads Authority (NRA).
Its pre-Budget report calls for tolls to be imposed on motorways in Galway, Wicklow and Kildare, while motorists in Dublin face the prospect of being forced to pay several tolls on the M50 for the first time.
The proposals are in a report commissioned by the Department of Transport in the summer. They will be sent to the Government in the coming weeks. They will arrive as the Government frantically searches for new sources of revenue in advance of a swingeing Budget.
If they decide to bring in the measures in the Budget, it could mean a new and substantial income straight into the Exchequer.
Among the key proposals are that the 31km of Dublin's M50 would be divided into sections that would be tolled. That would mean more motorists paying a toll as they would be charged on how much of the road they use.
The M50 has just one toll at the Westlink. A toll can cost up to €3 for a car. Under the new system, there could be as many as four sections and a charge, for example, of 75c applied to each section.
This means the overall toll would remain the same -- if the motorist drives the length of the M50.
For those who do not normally use the Westlink every day but do use sections of the M50, there would be a charge for the first time. About 110,000 motorists a day pay the toll at the Westlink.
Thousands avoid the charge because they don't pass the tolling point at Blanchardstown.
Other key proposals in the NRA's report include:
Tolls are unlikely on the M3 (Meath) and M4/6 as charges already apply on these roads.
The tolls could be levied within a year. News of such proposals will almost certainly spark an angry response from motorists who feel they are carrying a disproportionate burden of taxation.
Regular road-users -- including parents on school runs, shoppers and hauliers -- would bear the brunt of the new charges.
Hauliers would be worst hit, as they pay the highest tolls.
The AA said last night that tolling was an inefficient way of collecting extra revenue, and a survey of motorists it conducted in recent weeks found that 17pc took alternative routes to avoid paying a toll.
"There's a number of reasons why tolled roads are a bad idea," AA spokesman Conor Faughnan said.
"The moment you put a toll on a location, people will avoid that. It is an inherently inefficient way of collecting money. The M50 collected €95m last year, but spent more than €20m collecting it.
"Putting the tax on fuel gives you far more money without byzantine payment systems."
The Local Government Efficiency Review Group said in July that new tolls on national routes could raise between €60m and €100m to pay for new road schemes.
The NRA said last night it had been asked to compile a report on what tolling charges could be introduced.
"We're facilitating a request made by the Government and it is up to the Government to decide how or if it will be implemented," a spokesman said. "The report has not been submitted yet to the department."
Motorists pay about €184m a year in tolls across the country.