Prince William has labelled the illegal poaching of wild animals "economic sabotage" and warned that elephants, rhinos and tigers could "end up like the dodo" unless it is stopped.
He joined his father in co-hosting the wildlife conference with Environment Secretary Owen Paterson at St James's Palace.
Prince Charles earlier issued an impassioned plea, saying the fight against poaching was a "terrible race against time".
Mr Paterson warned that poaching was funding terrorism and other criminal activities and said "failure would be a shame on us all".
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