Motorists who leave their engines idling in central London could face a fine of £20 under plans to improve air quality.
Traffic marshals from Westminster City Council will patrol the streets of the West End, approaching motorists who sit in stationary cars with the engine running.
The penalty charge, which will go up to £40 if not paid within 28 days, will be a “last resort” if drivers refuse to turn off their vehicles on request.
High levels of pollution from vehicle emissions are linked to the deaths of thousands of Londoners each year.
Green campaigners welcomed the policy, which comes into force on May 1, saying it would help raise awareness of the pollution produced by idling.
But motoring groups warned it would be seen as a money-raising exercise unless it was properly enforced. Several councils, including Wandsworth and Camden, already have policed no-idling zones and information campaigns.
Boris Johnson brought in a number of no-idling zones in 2011, with traffic marshals targeting “hot spots” including taxi ranks outside major stations and coaches on Park Lane.
Westminster councillor Heather Acton, cabinet member for sustainability and parking, said: “We want to raise motorist awareness of the impact engine idling can have on the environment, with air and noise pollution affecting health, as well as it being an unnecessary use of fuel.”
It comes after the Mayor last week issued his first major public warning of high pollution in London, advising tens of thousands of people to cut back on exercise to protect their health.
The move to reduce unnecessary emissions has business backing.
Sarah Porter, of the Heart of London Business Alliance, said: “If our economic heartland is to retain its international appeal, attract new businesses and continue to grow, we must continue to introduce sensible and sustainable measures to improve air quality.”
Jenny Bates, Friends of the Earth’s London campaigner, said: “This should help cut pollution and raise drivers’ awareness of the lethal pollution they contribute to, and are themselves exposed to. However, the Mayor and Government must do much more to urgently clean up our filthy air and protect our health by tackling the main cause... too much dirty traffic.”
Neil Greig, director of policy and research at the Institute of Advanced Motorists, said the “key issue” would be how marshals enforced the fines.
“If they target private car drivers pulling up for a moment in relatively clean, modern cars... while ignoring old buses, coaches, large trucks, utility company vans or taxis... it will quickly be seen as yet another revenue-raising exercise,” he said.
