We need to prepare for the worst: Boss of Dutch port braced for impact of Brexit
Continental Europe's largest port has warned of additional expense and delays to trade as a result of Britain leaving the EU.
Dutch authorities have already begun recruiting customs officers in Rotterdam, with the port's boss estimating that "several hundred" will be needed to deal with the bureaucratic burden of Brexit.
Rotterdam Port Authority chief executive Allard Castelein warned of "huge" queues of lorries at ports on both sides of the English Channel, and said Brexit would raise the cost of goods imported into and exported out of the UK.
He raised doubts that a deal on "frictionless" trade can be reached by the official date of Brexit in March 2019.
Mr Castelein compared the situation to the "Y2K" Millennium Bug crisis, when authorities and companies spent millions preparing for the expected impact on computers of the arrival of the year 2000, without any certainty about what the scale of the problem would be.
"I think the implications of Britain leaving the European Union are underestimated," Mr Castelein told BBC Radio 4's Today programme.
"We will need several hundred customs officers. Any goods and any trade of volume between the UK and the continent will have to be cleared in Rotterdam or have to be cleared in the UK.
"Those processes will take significant amounts of time and will incur therefore cost, which will mean that the products will become more expensive and/or the incomes of the people shipping the goods will be reduced.
"It might mean a huge backlog of trucks at the various ports, which at this juncture we are not used to nor can we accommodate them."
According to Office for National Statistics figures, UK exports to the Netherlands totalled £31 billion in 2016, with imports of around £42 billion.
Much of the trade in goods is conducted via Rotterdam, with a significant proportion involving products which pass through the Dutch port before being re-exported to destinations around the world.
Mr Castelein backed efforts to avoid the erection of barriers to trade, saying: "I do believe we need to negotiate for the best, as frictionless as possible, because that will serve both countries and both sides of the Channel best."
But he added: "However, I do believe we need to prepare for the worst. From my understanding, it would appear to be unlikely that a little over 400 days from now such agreements will be in place.
"I compare the situation to the Y2K scenario. We need to prepare for an uncertain situation that will emerge the day Britain leaves the European Union.
"It is in my book a very serious issue and has my utmost attention."