The Scottish Justice Secretary has called for the transfer of more powers over drink-driving, before a debate at Holyrood next 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 is 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 areas such as breath-testing, drink-drive penalties and differential limits.
"This Government welcomes having the power to set the drink-drive limit but the Scotland Act was a missed opportunity. The very limited transfer of powers did not go far enough," Mr MacAskill said.
"We wanted a package to be devolved that would allow us to consider whether the police should be able to carry out breath-testing drivers anytime, anywhere and powers to consider changing the penalties for drink-driving.