The new crime carries a mandatory minimum 12 months disqualification, and summary conviction will lead to up to a year in prison or a £10,000 fine.

Conviction on indictment will lead to a maximum of five years in custody or a fine or both.

Drivers who get behind the wheel while disqualified, uninsured or with no licence will get an automatic 12-month ban and a maximum of two years behind bars.

Mr MacAskill welcomed the creation of the new offences by the Westminster Government and repeated his call for it to act on lowering the drink-driving limit. He wants the limit lowered from 80mg to 50mg and for police to be given powers to carry out random breath testing. 

He said: “A lower limit sends out a clear message that driving after you’ve had a drink isn’t acceptable.”

Isobel Brydie, of the Scottish Campaign Against Irresponsible Driving (SCID), said: “We’ve campaigned for these changes but it’s a pity they became law in 2006 yet it’s taken until now for prosecutors to announce they were being implemented.

“In the meantime many families will have found out how the death of a loved one is not taken into account in careless driving cases.”

Last week a van driver involved in the death a Scots cycling star was banned from driving for six months and fined £500. Relatives of Olympic hopeful Jason MacIntyre, 34, had wanted Robert McTaggart to be prosecuted for culpable homicide or causing death by dangerous driving.

And the family of Jason Ness, 17, who died in a crash, hit out after joyrider Philip Tod, 21, was fined and banned for six months.