Penalties for drivers using hand-held mobile phones at the wheel will increase this week.
From Tuesday, the fixed-penalty fine for offenders will double from £30 to £60.
Also, for the first time, those caught using hand-held mobiles will get three penalty points on their licence.
Courts will have the powers to give a maximum fine of £1,000 or £2,500 in the case of a driver of a bus, coach or goods vehicle. Offenders could even be disqualified from driving.
Recent Department for Transport figures show that while more than 90% of people agree with the mobile phone law, around 20% of drivers admit to breaking it.
Research shows that if you are using a mobile phone while driving you are four times more likely to crash.
The ban on the use of hand-held mobiles while driving was introduced in December 2003.
The increase in penalties also applies to the charge of not having proper control of a vehicle - a measure which can also be used where a driver has been distracted by using a hands-free mobile.
Police forces have warned that they will be cracking down on offenders. Inspector Richard Pryce, from Devon and Cornwall Police's traffic department, said: "It is unacceptable for anyone to drive a vehicle on a road while using a hand-held mobile phone.
"We will be robustly enforcing the new legislation and anyone who is caught using a hand-held phone while driving will be dealt with accordingly. With penalty points now being applied for the offence, you could lose your licence."
