If Britain leaves the European Union with no deal in place it will cause the Dutch government at least €2.3 billion in direct costs through 2023, the Court of Audit said on Monday.

The court, which performs official analyses for government decision-making purposes, noted that the Cabinet and much of Dutch industry have been preparing "intensively" for Brexit since 2016, but the country's customs office still may not be ready in time in a "worst-case scenario."

Britain is the Netherlands' third-largest trading partner after Germany and Belgium.

The figures released by the agency on Monday do not take into account lost revenue if Britain's departure accompanies a wider regional recession. They complement the largest official study on indirect costs to the Dutch economy to date, conducted by the country's Economic Policy Analysis (CPB) bureau in 2016.

That study found that trade lost as a result of Brexit would reduce the Dutch economy by an amount increasing to 1.2 per cent of GDP annually by 2030, or €10 billion.