A DECISION over whether the next Scottish Parliament will be in place for three or five years will be taken at Holyrood.

The Scotland Office has said that powers to set the date of the next Holyrood election after 2016 will be transferred north under a fast-tracked legal measure known as a Section 30 order. It means that voters will know how long they will be electing MSPs for when they go to the polls next May.

The issue is currently unclear as Holyrood usually sits for a four-year term, meaning another election would have been due to take place in 2020. However, this would have meant a clash with the next General Election, which is not allowed. It leaves open the prospect of a Holyrood election being held in 2019 or 2021.

A number MSPs believe the next parliament should only sit for three years, to avoid a repeat of the problem in 2025 and return Holyrood to a four year cycle.

Mr Mundell said it was a matter of agreement between the UK and Scottish governments that voters should know the length of term they will be electing MSPs in next year's election.

"This is a sensible move which ensures clarity for voters in Scotland by giving the Scottish Parliament the power to set its own parliamentary terms," he said. "It will ensure Holyrood elections take place separately from others in future."

Wider controls over Scottish elections will be included in the Scotland Bill, designed to implement the post-referendum Smith Commission recommendations on further devolution.

The Scottish Parliament's Presiding Officer Tricia Marwick, who The Herald revealed last month had written to the UK Government to press the issue, welcomed the announcement, pointing out that party leaders at Holyrood backed the move.

She said: "I wrote to the Secretary of State for Scotland, with the support of all party leaders, about the May 2020 election date clash with Scottish and UK parliaments. I am pleased he has agreed to the request for a section 30 order.

"When the people of Scotland vote in 2016, they need to know how long the term of office will be for those they elect."

A Scottish Government spokeswoman said: "The Scottish Government is working closely with the UK Government to agree the terms of an Order that will ensure that the Scottish Parliament can determine the date of its own election following the one in 2016, to avoid a clash with the UK general election in 2020."