The Justice Secretary has called for the transfer of more powers over drink-driving, before a debate at Holyrood this week on plans to reduce the limit.

MSPs will debate the Scottish Government's proposals to lower the existing blood/alcohol limit of 80mg/100ml to 50 mg/100ml, which are currently the subject of a public consultation.

Kenny MacAskill has written to UK Transport Secretary Patrick McLoughlin asking for the devolution of additional powers over breath testing, drink-drive penalties and differential limits.

"We wanted a package to be devolved that would allow us to consider whether the police should be able to carry out breath testing of drivers any time, anywhere, and powers to consider changing the penalties for drink-driving," Mr MacAskill said.

"We also called for the chance to consider differential drink-driving limits. For example, for young and novice drivers.

Mr MacAskill's plea comes after the Reported Road Casualties Scotland 2011 report showed an estimated 750 casualties including 20 deaths were due to drink-drive accidents in 2010.

A debate on the Scottish Government's proposals to reduce the drink-drive limit will be held on Thursday at Holyrood.

Mr MacAskill said: "We must take action to reduce the risk on our roads. We believe the current limit has had its day. The time is right for a change that will bring Scotland in line with the vast majority of Europe.

"As we enter the final phase of our consultation, I would urge as many people as possible to have their say before November 29."