A month after the end of the Brexit transition period, authorities say the volume of goods coming into Irish ports from the UK remains at around 50% of normal.
However, the quantities of freight are continuing to gradually build week-on-week, state agencies report, with an 11% increase in movements last week compared to the previous seven days.
Concerns over post-Brexit paperwork, as well as delays at ports and changes in supply chains have also led to a 100% year-on-year increase in the amount of freight trade moving directly between Ireland and continental Europe.
Authorities say goods continue to move reasonably freely through Irish ports, with 80% of incoming vehicles arriving from the UK being green routed through, meaning they aren't being stopped for further checks.
However, volumes remain far lower than normal due to pre-Brexit stockpiling, rerouting of goods onto direct routes between Ireland and the continent, lower demand for some items due to Covid-19 restrictions and the additional checks.
Hauliers, freight transport companies, importers and exporters say they remain extremely concerned about the amount and complexity of new paperwork and systems introduced after the UK became a third country.
They think many UK companies exporting into Ireland were woefully underprepared for the end of the transition period on 31 December and have still not got to grips with complex new requirements.
As a result, they say large quantities of freight remain stuck at distribution centres and warehouses in the UK.
Irish hauliers say this means that they are often returning from the UK with empty trailers, a situation which cannot be sustained.
Last week the Irish Road Haulage Association warned the Government and European Commission that unless there is a loosening of the regulatory requirements, there will be a complete standstill in trade between the two islands.
In an operational update on the situation one month on from the end of the transition period, the Government acknowledged there had been some issues getting goods through.
"Through engagement with transport and logistics companies, we are aware of problems and backlogs in the supply chain, particularly in GB," it said in a statement.
"We know that the introduction of new import and export regulatory requirements alongside new checks and controls on trade between the EU and UK, excluding Northern Ireland, adds additional burdens on companies and our Departments and Agencies are continuing to engage with companies and haulage and logistics companies to help them work through these new checks and controls."
However, it added that it had been reassured during ongoing engagement with the retail sector that significant shortages have not materialised.
"Supply chains have been built up over time and will take time to readjust," it said.
"Any isolated issues are being worked through and we continue to be assured by retailers that supply is robust and strong at shelf level and stores are well stocked."
The Government also said that its departments and agencies continue to encourage businesses and individuals to engage with them on the new trading arrangements.
It also reminded firms that they should try to identify and communicate with the important businesses in their supply chain.
Revenue said that it has successfully processed 760,000 import declarations since the start of January, with a further 155,200 export declarations also put through the system.
There have been around 17,500 freight vehicle movements into Ireland from Britain over the same period and 16,900 freight vehicle movements out of Ireland to Britain.
The heightened demand for additional capacity on direct routes to continental Europe has led to an increase of 36 sailings a week on these routes compared to the same time last year.