The number of motorists caught using a mobile phone illegally has almost halved since penalties for offenders were doubled, new figures show.
Around 39,000 fixed penalty notices (FPNs) were issued to drivers between March and December last year compared with 74,000 during the same period in 2016, according to police data.
The 47% decline is due to a combination of harsher punishments, road safety campaigns and a lack of enforcement due to reductions in traffic officer numbers, according to the AA.
The figures were obtained by the breakdown rescue firm after it submitted Freedom of Information requests to all of the UK's 45 police forces. It received responses from 41.
Since March 1 last year, motorists caught using a handheld phone have faced receiving six points on their licence and a £200 fine - up from the previous penalty of three points and £100.
Drivers can lose their licence if they receive 12 points within three years, or six points in the first two years after passing their test.
March saw the most FPNs issued for mobile use in 2017 as many forces conducted a crackdown on distracted drivers, with more than 8,500 caught.
The lowest monthly total was 1,400 in December as police focused their efforts on drink-drivers over the festive period.
AA president Edmund King said: "It will take time for a wholesale change in attitudes to really take effect.
"While some have got the message and changed their behaviour, many drivers still believe they won't get caught."
Separate RAC research found that nearly one in five (19%) firms say their employees have been involved in an accident after using a phone illegally while driving for work.
A survey of 1,000 UK businesses revealed that 5% admit this happens "on a regular basis".
Department for Transport figures show 780 people were injured in accidents in 2016 when a driver was distracted or impaired by their phone, up 10% on the previous year.