A bag containing around £300,000 cash was discovered in a van stopped by roads policing officers in Ashford.
The vehicle came to their attention whilst being driven on the M20 between Junctions 8 and 9, at around 9.20am on Tuesday 13 April 2021.
A search of the van was then carried out at the Eureka leisure park, where the officers found a quantity of cannabis along with a holdall stuffed with banknotes.
The driver, a 40-year-old man from Nottinghamshire, was arrested on suspicion of money laundering, possession of cannabis and driving whilst under the influence of drugs.
He has since been released on bail pending further enquiries until Friday 7 May 2021.