The M8 should be upgraded to a three-lane motorway all the way between Glasgow and Edinburgh, a Glasgow MSP has said.

Annie Wells, Conservative MSP called on Transport Secretary Michael Matheson to secure funding to add more capacity on the country’s busiest motorway.

She said there is currently disruption to the main rail line between cities and the motorway doesn’t have the capacity to cope.

There is currently disruption due the recent collapse of part of the Union Canal on to the line near Falkirk High station requiring major repairs.

Ms Wells said: “The key to increased economic activity is having transport links to support businesses and workers in the area, which is why we are calling for an acceleration of infrastructure projects, including a three-lane M8.”

Mr Matheson, however dismissed the idea and said it was “silly” and “childish”

He said: “I’m aware of the Conservative commitment.”

However, he added adding more lanes to the M8 would mean other transport improvement projects couldn’t go ahead.

Mr Matheson said: “Introducing a third lane to the M8 would mean no money for the upgrade of the A77 or the A75, for investing in the A96 in the north-east, for completing the dualling of the A9, or for the other big strategic investments that we are making in health and education.”

He said the policy was “crafted on the back of a fag packet” and added it was a “silly and childish approach”.

Earlier Mr Matheson said almost 1km of the main line was swept away during the period of adverse weather.

He said: Restoring the route is a significant undertaking from an engineering point of view.