Customs staff are letting down legitimate retailers by allowing illegal duty-free imports through the UK’s largest airport.

Staff at London’s Heathrow airport had been instructed to take a zero-tolerance approach to undeclared tobacco and alcohol, and to seize all items from travellers who brought back more than the legal limit.

A report by the independent chief inspector of borders and immigration revealed that airport staff were not abiding by those rules, allowing excess duty-free items to pass through customs.

Legitimate retailers need to put more pressure on Customs, trading standards and MPs to make sure that loopholes are closed to smugglers

Hitesh Pandya, owner of Toni’s News in Ramsgate, Kent, said Customs officers were failing retailers.

“They should be doing spot checks, and the link between the groups that are supposed to be monitoring smuggled goods should be stronger,” he said.

“It allows illicit products to be sold in all sorts of places – I know of a butcher’s shop that’s doing it, and people are using social media to sell illegally.”

Pandya argued that Customs knew the market was changing, but made excuses about lacking manpower.

“Legitimate retailers need to put more pressure on Customs, trading standards and MPs to make sure that loopholes are closed to smugglers,” he said.

An HMRC spokesperson said: “HMRC fully supports the steps taken by Border Force to ensure all Heathrow staff are aware of the importance of enforcing limits on cigarettes and alcohol.”

Last month, the Tobacco Manufacturers’ Association launched an airport-based campaign to warn holidaymakers of the consequences of bringing excess duty-free into the UK.