A large quantity of drugs was found during a route check for coronavirus regulations.
At about 10.55am on Monday, North Yorkshire Police officers were on patrol on the A1(M) near Scotch Corner.
A grey VW Passat was stopped, and the driver spoken to.
While talking to the driver, officers noticed a strong smell of cannabis.
A search of the vehicle revealed several shopping bags full of suspected cannabis, with a street value of tens of thousands of pounds.
The car itself was also seized for being driven uninsured.
The driver, a 25-year-old man, was arrested on suspicion of possession with intent to supply cannabis, and driving without insurance.
He has been released under investigation while enquiries continue.