Anyone caught talking or texting on a handheld phone behind the wheel faces a fine from £30 to a maximum of £1,000.

Police are expected to go easy on some drivers for two months, to give them time to get used to the new law, as a poll showed many don't know about it.

Road safety charities say at least 20 people have died from mobile-related accidents, and many more have been hurt because of people talking and driving.

Not enough

But a survey showed that 94% of drivers hadn't even heard of the new law, even though at least a quarter of them admitting talking or texting on their mobiles while driving.

However many road safety experts say banning mobiles is not enough, and that hands-free kits must be illegal too.