Government has no idea of export levels passing through UK
There are no figures for the amount of Irish exports that travel through the UK on their way to other countries.
Despite warnings from Foreign Affairs Minister Simon Coveney that companies using Britain as a bridge to other locations could be badly affected by Brexit, no Government department has established the level of trade at risk.
The revelation will cast doubts over the preparedness in official circles as the UK tries to move the Brexit negotiations onto the issue of customs.
Fianna Fáil's Kevin O'Keeffe said he finds it "simply inconceivable" that the Government does not know the level or amount of goods and services exported to Europe overland through the UK.
Depending on the final Brexit deal between the EU and UK, such goods could be subject to custom tariffs.
In response to queries from the Fianna Fáil TD, Taoiseach Leo Varadkar said: "The country of final destination is recorded as the country of export in the merchandise trade data. There is no data available on the route taken, or transit country of the goods."
Mr O'Keeffe said the statement "beggars belief".
"Brexit will place limitations on many Irish exporters, and increased bureaucracy as a result of potential customs checks will make using this route more cumbersome and potentially more expensive.
"One would have thought that the Taoiseach, or someone in Government, would have looked into this issue due to the potential implications of Brexit," the Cork East TD said.
He called for deeper analysis "of the myriad challenges posed by Brexit".
Mr Coveney recently warned that subjecting goods passing through the UK to customs tariffs would not work for Ireland. His department told the Irish Independent about 80pc of Ireland's exports are transported to the UK, either for direct use or for onward transit.
"The Government's extensive engagement with stakeholders, including through the All-Island Civic Dialogue, has also highlighted the land bridge with the UK and the status of goods in transit as a key priority issue for the transport sector and for businesses exporting from Ireland," a spokesperson said.