Motorists caught using a mobile phone while driving are set to face tougher punishments.
Penalty points will rise from three to four and fines will go up 50% to £150 under Government proposals.
But the Institute of Advanced Motorists (IAM) warned that the move would not have a "dramatic impact" unless there were more traffic police officers to enforce the law.
Under the measures, drivers of larger vehicles such as HGVs would receive six points for being caught on a hand-held phone - up from three - because the consequences of an accident can be much more severe.
Drivers can be banned from the road if they receive 12 points within three years.
In 2014 the use of a mobile phone was a contributing factor in 21 fatal accidents and 84 which were classed as serious, according to Department for Transport (DfT) statistics for Britain.
Transport Secretary Patrick McLoughlin said: "Using a mobile phone at the wheel is reckless and costs lives - I want to see it become a social taboo like not wearing a seatbelt.
"We will take action to tackle this persistent problem, with an emphasis on the most serious offenders."
Most people caught for the first time will be given the opportunity to avoid points on their licence by taking an educational course which focuses on the effects of holding a mobile while driving.
The IAM's director of policy and research, Neil Greig, praised the Government's desire to improve road safety but claimed harsher punishment for mobile use will not have a significant effect.
He said: "We believe increasing penalties for hand-held mobile phone use will not have a dramatic impact.
"What we need is an increase in traffic police officers who enforce tougher regulations, in which motorists would fear using a mobile phone at the wheel because they'll get caught, as opposed to just getting higher fines."
In October the RAC published analysis of Ministry of Justice data showing that prosecutions for the offence are down by almost half in five years, despite a study showing the practice is more common.
Just 17,414 prosecutions for drivers using their phone at the wheel were launched in magistrates' courts in England and Wales last year, down by 47% from 32,571 in 2009.
This is despite a 2014 DfT study which found that 1.6% of drivers in England were observed using a mobile, up from 1.4% in 2009.
AA president Edmund King said drivers have "demanded action" over the "epidemic" of hand-held mobile use behind the wheel, while RAC chief engineer David Bizley described the practice as "a real danger".
A 27-year-old man from the Isle of Wight was jailed for six years in January for killing another motorist while texting. A woman, 36, was handed a five-year prison sentence in July for killing a cyclist in Fife after using her mobile while driving.
Last year a 31-year-old woman was given a six-year jail term for crashing into the back of a car and killing its driver while she used two mobile phones.
The Government will hold a consultation over the mobile phone proposals, which form part of its road safety plan to be published next week.