All new models of cars and vans should be equipped with special daytime lights from 2011 to improve road safety, the European Commission says.
The EU directive - not yet law in all 27 member states - means vehicle lights will also be more environment-friendly, the commission says.
The Daytime Running Light (DRL) comes on automatically when the driver starts the engine.
Industry executives have backed the proposal, the commission says.
It speaks of “very positive” results for road safety in EU countries where DRL is already mandatory, such as in Scandinavia.
The directive envisages that from 7 February 2011 all new types of passenger cars and small delivery vans will have to have DRL. Trucks and buses will follow from August 2012.
When it is dark, the driver has to switch on the headlamps manually - in that case, the DRL goes off automatically.
“This will make a positive contribution to our goal of reducing fatalities on European roads whilst being more fuel efficient then existing lights,” commission vice-president Guenter Verheugen said on Wednesday.
The DRL’s energy consumption is just 25-30% that of the normal driving light and when using LED (Light Emitting Diode) technology for DRL, the energy consumption is only 10% of the current average, the commission says.
It argues that DRL makes vehicles more visible to all road users.
But the Conservative transport spokesman in the European Parliament, Timothy Kirkhope MEP, warned that too much light could distract drivers and put cyclists and pedestrians at greater risk.
He called for an independent assessment of the technology before any EU-wide approval of DRL.