By Thomas Burrows for MailOnline
Published: 09:09 GMT, 7 November 2017 | Updated: 09:25 GMT, 7 November 2017
Motorists who leave their car running on icy mornings to warm up the engine and clear the windscreen could face a £40 fine under a little-known rule.
Drivers are warned that leaving a car 'idling' for more than a couple of minutes wastes fuel and they could slapped with a fixed £20 fine - or £40 if not paid within three weeks.
Many councils now enforce the 'stationary idling offence' which was quietly introduced by the government in 2002.
Motorists who leave their car running on icy mornings to warm up the engine and clear the windscreen could face a £40 fine
The fines enforce Rule 123 of the Highway Code, which states: 'If the vehicle is stationary and likely to remain so for more than a couple of minutes, you should switch off the engine to reduce emissions and oil pollution.'
If the vehicle is