Shortly before midnight on Wednesday, 24 March armed officers stopped a vehicle on Twickenham Road, near to the junction of London Road, Isleworth.
During the search of the vehicle, two loaded firearms were recovered.
The driver of the vehicle, a 26-year-old man, was arrested at the scene on suspicion of possessing a firearm with intent to endanger life.
Detective Inspector Jim Casey, from the Met’s Specialist Crime Command, said: “This operation continues to show we will relentlessly target those involved in serious crime in order to protect the communities of London.
”These weapons were clearly intended to be used in crime and could have resulted in serious injury or even death.”
The man is currently being questioned by detectives at a west London police station. Enquiries continue.