New electronic border control options that would allow vehicles to cross from Northern Ireland to the Irish Republic without stopping are being explored.
They are being developed by Irish Revenue officials, and informal contacts have already taken place with the UK, the Irish Independent has reported.
The head of Irish Revenue's Customs division said the plan is in its early stages and could take a number of years to fully build.
Anthony Buckley, deputy director general of Irish Customs with the Revenue Commissioners, said the aim is to develop a system whereby a truck can drive from one end of the island to the other without having to stop.
"Even if there's a free-trade agreement (between the UK and EU), we'll still need to know what is being traded, what's crossing the border," Mr Buckley told a Brexit briefing organised by the Irish Exporters' Association (IEA).
"Our design challenge is that a truck should be able to drive from Cork to Belfast or from Holyhead to Galway, without stopping. That would be the ideal, and we want to achieve that.
"We're starting the design process at the moment. We've already started the scoping and we will be building, but it will take us two or three years to build."
Revenue's aim is to ensure that information about a truck's load, for example, could be put into a computer on this side of the border, and then be automatically conveyed to the UK authorities.
The movement of the truck could then be monitored in an eFlow-style electronic camera system similar to Dublin's M50.
Customs clearance facilities would have to be provided, Revenue believes, but they don't have to be at the border. Existing tax offices in border areas may serve the purpose. But at the border itself, vehicle examination areas may be needed. Spot checks of vehicles may have to take place to combat smuggling and fraud.