PLANS to bring in new drug driving limits will improve road safety in Scotland, the Justice Secretary has said.

But it would have been preferable for all power over the proposed new offence to be given to Holyrood, Kenny MacAskill said.

The UK Government has launched a consultation to make it easier to prosecute drug-drivers. A zero-tolerance limit for eight illegal drugs, including cannabis, ecstasy, cocaine and heroin, is proposed. Limits would also be set for controlled drugs that can affect ability to drive, such as temazepam, diazepam and methadone.

But while the Scottish Government has the power to set the drug-driving limit, the responsibility for other matters related to drug driving is with Westminster.

Hailing the new limits, Mr MacAskill said: "It will no longer be necessary to prove impairment on a case-by-case basis in order to obtain a conviction."