Loophole is rule designed for long-haul sailors
The use of non-EU workers on some Irish fishing vessels involves a loophole in an EU law that is aimed at facilitating the merchant marine sector.
The regulation allows non-EU marine workers up to 48 hours to transit through EU member states to join vessels bound for international waters.
The regulation was drafted to facilitate Asian, African and South American workers employed on oil tankers, cruise liners and giant freighters. These would often visit EU ports before departing for long-haul duties.
Brussels designed the regulation to allow them to join vessels while in EU ports and before they departed on long-haul routes through international waters.
London is one of the most popular transit points, as the UK straddles all the major sea approaches to busy northern European ports.
However, the EU confirmed that the regulation was not designed for fishing vessels, where crew regularly return to the same ports.
London is central to the migrant allegations, given that all non-EU fishing workers arrive in the UK capital before being transferred to Ireland.