Drivers caught using a mobile phone illegally for the first time will no longer be able to avoid getting points on their licence by taking a remedial course, under plans announced by the Department for Transport (DfT).
A number of police forces currently offer workshops to educate motorists about the dangers of making a call while they are behind the wheel.
But the DfT believes this is not a tough enough measure to deter people from answering a call while they are driving or to change their future behaviour.
Prime Minister Theresa May said she wants to make using a mobile phone at the wheel as socially unacceptable as drink-driving.
The plan was announced in the DfT's response to a consultation on the punishments handed out to motorists caught using a hand-held phone.
The document confirmed the Government's intention to double the fine from £100 to £200 and increase the penalty points from three to six, which first emerged in September.
It comes shortly after the jailing of lorry driver Tomasz Kroker, who was scrolling through music on his phone just before he ploughed into stationary traffic on the A34 in Berkshire, killing Tracy Houghton, 45, her sons Ethan, 13, and 11-year-old Josh, and step-daughter Aimee Goldsmith, 11.
Steve Gooding, director of motoring research charity the RAC Foundation, said: "By ruling out courses and doubling the fine, ministers are reflecting public concern and showing they want to stamp out a potentially lethal activity before it becomes entrenched behaviour for a growing number of drivers."
The number of fines issued for motorists caught using a mobile phone illegally has plummeted by 84% since 2011.
Just 16,900 drivers were handed fixed penalty notices in relation to the offence in England and Wales last year, compared with 123,100 in 2011, Home Office data shows.
Motoring groups believe the decline is due to a 27% fall in the number of full-time dedicated roads policing officers in England and Wales (excluding London) between 2010 and 2015.
DfT figures show that a driver impaired or distracted by their phone was a contributory factor in 440 accidents in Britain last year, including 22 which were fatal and 75 classed as serious.
Mrs May said the Government would work with the public to "raise awareness" of the dangers of driving and dialling.
And she said that punishments for drivers who kill and maim people because their attention is on their phone should be made to "fit the crime", as a deterrent to other motorists.
Ministers are launching a consultation on dangerous driving offences.
Speaking during a visit to India, Mrs May said: "Sadly we have seen too many times the devastating and heart-breaking consequences of using a mobile phone while driving. A moment's distraction can wreck the lives of others forever.
"We are determined to make our roads safer by taking action against those who flout the law and put other people at risk. That's why we are doubling the penalties for using a mobile while driving, with tougher measures due to take effect next year.
"We will also launch a consultation on dangerous driving offences by the end of the year.
"The sentence should fit the crime for those who kill or seriously injure on our roads and it should deter other drivers from causing needless harm just for the sake of taking a call or sending a text."