An angry motorist said he was targeted by clampers who lay in wait at a petrol forecourt as he left his car to withdraw money.
Charles Jones, 28, went to fill up his car at the Esso petrol station in Victoria Road, North Acton, but realised he did not have enough money.
Not wanting to pay the charge at the forecourt ATM he decided to use the free cash machine across the road.
But when he returned moments later, his car was clamped and he had to pay a £150 release fee.
Mr Jones who practises with his band in Ealing said it was a 'dirty tactic' used by the clampers.
He said: "I was furious about being clamped as I had only been gone a few minutes.
"They saw me park up and leave the car and I'm baffled as to why they couldn't have warned me.
"When I said I wasn't going to pay and was there 15 minutes, they told me I faced a £350 fine.
"I was a customer of the petrol station and don't see how they can get away with this."
Michael Obi, manager of Parking Solutions Limited said it was necessary to use clamps to stop people parking and shopping in Tescos across the road.
Mr Obi said: "We have big signs warning motorists about the parking restrictions and if they leave their cars, it's subject to removal.
"Every driver who doesn't comply will be clamped as they may be causing an obstruction and acting against health and safety regulations. Parking is available for customers while on the premises and we understand the ATM on site does charge but five minutes is rarely five minutes.
"The public don't realise the problems the garage faces with motorists parking to use the Tesco store and this is a necessary measure."
A spokeswoman from Esso said: "Parking spaces are for the use of customers while at the service station.
"Regrettably, some drivers are parking their vehicles at the site for prolonged periods and visiting other facilities in the area.
"We have therefore engaged the services of a professional clamping company to enforce the parking restrictions, which are clearly signposted around the site."