Boris Johnson’s kipper is very much a red herring, Brussels says.

The Tory leadership contender’s brandishing of a kipper during a speech in London on Wednesday night to lambaste unnecessary EU regulation was completely misplaced, an EU Commission spokeswoman said on Thursday.

Regulating the packaging of processed food, as opposed to fresh fish, is a matter for national governments, she pointed out.

Johnson had claimed EU rules meant kippers from an Isle of Man producer could not be posted out to consumers without a plastic ice pillow, an extra cost burden on smokers.

Using the plastic-wrapped kipper as a prop to attack both the EU and Brexiteers in Ukip, he told the crowd of Conservative members in the final leadership hustings debate: “We will bring the kippers back. It’s not a red herring.”

The kipper producer, he claimed, was “utterly furious” at the packaging costs imposed on him by the EU.

“Pointless, expensive, environmentally-damaging health and safety, ladies and gentlemen,” Johnson said.

Debunking the former foreign secretary’s assertions, the EU spokeswoman said: “While the food business operator has an obligation to meet the microbiological requirements to ensure the safety of its food ... the sale of products from the food business operator to the final consumer is not covered by EU legislation on food hygiene.

“”The case described by Mr Johnson falls thus purely under UK national competence.”

Old Brussels hands say the claim brought back not-so-fond memories of Johnson’s days in Brussels as a Daily Telegraph correspondent in the 1990s. Then he pioneered a new form of Eurosceptic journalism epitomised by usually false claimsm, such as that Brussels was setting rules for the curvature of bananas.

What Johnson did not admit to his supporters on Wednesday, however, is that the decision of the UK to leave the EU will bring a prohibition on the export into the EU of kippers, and all animal-based products such as meat and cheese, unless they emanate from certified producers.

Travellers determined to continue to enjoy their traditional British breakfast on holiday in Spain will find kippers packed in their luggage confiscated at Calais.