Motorists who use a hand-held mobile phone behind the wheel face stiffer penalties from Tuesday.

For a first offence they will get three penalty points on their licences while fines double to 60 pounds.

The new rules will also hit drivers who use a hands-free mobile kit but fail to have proper control of their vehicle, and driving instructors, who are not allowed to use a mobile phone while giving lessons.

Now an endorseable offence, with offence code CU80, motorists found flouting the rules could also see their car insurance costs rocket.

AA Insurance warned that drivers who end up with points on their licence from using a mobile could end up paying more than four times the fine through higher premiums.

"Insurers will take this issue seriously," said motor insurance head Janet Pell. "There is an irrefutable link between the use of mobile telephones and claims."

It has been illegal to use a hand-held mobile behind the wheel since Dec. 1 2003.

Home Office figures show that almost 74,000 fixed penalty notices were issued for illegal use of a mobile phone while driving in 2004.

But around half-a-million motorists break this law every day, according to the RAC Foundation.

Road Safety Minister Stephen Ladyman hoped the increased penalties would act as a greater deterrent.

"Using a mobile phone while driving is dangerous and selfish," he said. "Research proves that drivers talking on a phone have even slower reactions than someone driving under the influence of alcohol."

Police forces and road users welcomed the move.

Dorset Police said it would increase enforcement measures until the end of March in support of the enhanced penalties.

Cyclist Ben Davies, 35, said: "I have been endangered more times by motorists using mobiles while cycling in London than I can remember.

"These new laws should go some way to making motorists think before holding mobile telephones and driving."