GREEN MSP Mark Ruskell was forced to “correct” a BBC presenter twice during an interview on road safety.

It comes as Wales becomes the first country in the UK to reduce speed limits in built-up areas from 30mph to 20mph as of Sunday.

The move has been backed by the United Nations and environmental and road safety groups, although opposition politicians have declared it a “war on motorists”.

Ruskell pointed out that in Edinburgh, where there has already been a rollout of the policy, there’s been a 30% reduction in crashes and accidents since its introduction.

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“That is really significant. It’s not just a question of lives saved, there are many life-changing injuries that take place veery single year and this is about avoiding those tragedies and accidents”, Ruskell told Good Morning Scotland.

In response, host Martin Geissler said: “The point has been made that lots of people die on the A9, 13 killed last year on the stretch between Perth and Inverness.

“And you don’t want to dual that. If you were, you know, really serious about saving lives on the roads you wouldn’t be opposing the dualing of that stretch of dual carriageway.”

Ruskell replied to say this was “not quite true” and that “what we’ve said is that there is a case for dualing certain sections of the A9”.

Geissler interjected to say the Scottish Greens “didn’t want the whole plan to go through” to which Ruskell (below) responded: “’I’ve also been working with communities who want to see junction improvements on the A9 and we’ve seen accidents on the A9 at junctions.

The National: Mark Ruskell speaking in Holyrood

“We’ve seen accidents as well on dual section of the A9 but 20mph is a simple approach we can take nationally.

“It’s been shown to work in Edinburgh, it’s been shown to work very successfully in the Borders.

“It is reducing casualties, it is making our communities feel safer and friendlier. It is something we should be rolling out across Scotland.”

Geissler then cited a report from the Welsh government and claimed that this said 20mph zones could lead to a £4.5 billion hit to the economy.

Ruskell replied: “Well that’s not quite right. The Welsh study showed there would be an economic benefit over 30 years if you add in the economic cost of journey times being longer.”

Geissler said the report highlighted longer journeys could cause a “substantial economic disadvantage”.

Ruskell replied: “There are some problems with the way these economic costs are worked out. The UK Treasury’s analysis counts any single delay as an economic impact to the economy but it’s a somewhat spurious way of working things out.

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“It would be the equivalent of me saying to everyone listening if you spend an extra minute drinking your coffee in the morning that that will cause the economy a massive cost in the next 30 years.

“It’s not real-world costs.”

The Welsh report also explained: “The estimated cost to the economy of £4.5bn over 30 years may not be an accurate reflection of the true cost.

“The slightly longer travel time was the only negative economic impact identified.”