Prince William was greeted by the organisation’s chairman Lord William Hague during the visit to the Royal Mail’s Worldwide International Logistics Centre at Heathrow Airport, on Thursday.
The pair were invited on a tour of the lock-up to see the fight against the illegal wildlife trade in action.
The room contained recently seized contraband by UK Border Force, including weapons, packets of cannabis, MDMA and cocaine, as well as wildlife products.
Noticing the strong smell of cannabis in the room, William joked: “We had better get out before we have a drugs test!”
Clive Perry, the senior manager with Border Force who showed the William around the seizures, said: “I think my officers have got immune to it in there, to be honest. We process it and move it out as quick as we can.
“He [Prince William] did comment on it – it’s something you can’t ignore. I think the smell of paint in there had gone, because we had it decorated for his arrival, so the cannabis has overwhelmed it.”
UK Border Force officers explained how they are trained to spot suspicious packages and William observed them looking at incoming mail through an X-ray scanner.
The Duke was shocked at the amount of items in the room and was shown the most recent seizures, which included butterflies, crocodile leather items and ivory necklaces.
In 2017 Border Force made 139 seizures of ivory items on export through Royal Mail Postal Services from the UK.
Before departing, William was also presented with a special commemorative set of Royal Mail stamps demonstrating the work of United for Wildlife and the Transport Taskforce.
On Wednesday night, the Duke appeared on a DIY SOS: Grenfell TV special where he helped Nick Knowles and the team to redecorate the community’s new boxing club.
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