The dualling of the A9 will finally be finished by the end of 2035, a decade later than initially promised, MSPs have been told.

Màiri McAllan, the Cabinet Secretary for Transport, Infrastructure and Connectivity of Scotland, said a “rolling programme of construction” with sections opened “progressively" would start in the new year.

The minister told parliament that nearly 50% of the road is expected to be dualled by the end of 2030, rising to 85% by the end of 2033, with the final section expected to open by the end of 2035.

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Highland MSPs expressed some scepticism. They said their constituents would have little faith in the promises, given previous pledges had failed to materialise. 

A promise to fully dual the single-carriageway between Perth and Inverness by 2025 was first made in a 2007 SNP manifesto, with plans to widen around 80 miles of single-carriageway in 11 sections along the road formally made in 2011.

But just 11 miles in two sections have been dualled in the last 12 years.

Last year 13 people lost their lives on the A9, of those 12 were on single-carriageway sections.

Ms McAllan told MSPs: ”This programme has faced challenges, and I acknowledge that it has not progressed at the pace we would have liked. 

“They have of course been particular challenges with sky-high inflation causing slippage in a major capital project. 

“However, the A9 is the backbone of Scotland, it must be safe, it must be reliable, it must be resilient and that is what this government will deliver.” 

Work on a stretch of the road between Tomatin and Moy – roughly six miles – is due to begin in summer 2024 and be completed by the end of 2027.

The total cost of the programme is now estimated at £3.7bn at April 2023 prices, equivalent to £2.45bn at April 2008 prices. 

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Tory MSP Murdo Fraser said "too many lives have needlessly been lost" because of the lack of work on the road.

"More will die as a result of the delays we have heard about today," he added.

“At best we will be waiting another 12 years for this project to be completed, and that is the most optimistic outcome we can hope for.”

Ms McAllan said the “complex” project now has a comprehensive delivery plan.

She said it has been affected by external factors such as the “financial volatility” under the Conservative UK Government.

Labour’s Alex Rowley said the SNP first committed to dual the A9 in 2007.

He said: “With the new date of 2035 for completion between Perth and Inverness, some 28 years after the initial promise, one has to wonder how on Earth can the Cabinet Secretary say with a straight face that the Highlands can have confidence?”

Ms McAllan said the Government has a “proud history of delivering major projects”.

SNP backbencher Fergus Ewing, who has long called for the A9 dualling project, said he will continue to remain “sceptical".

"It is said that to be prepared is half the victory and I think she will agree we're not as yet fully prepared.

"So will she acknowledge that many, including myself, will continue to remain sceptical until they see even the diggers on the road?

"And that the statement today, whilst on the face of it encouraging, involves a huge amount of work ahead, and so in conclusion, there must be no more slippage, no more delays, and no more broken promises."

The Minister praised her colleague for his "determined campaigning" on the A9.

Ms McAllan said: "I wouldn't expect Fergus Ewing to be anything other than sceptical, helpfully sceptical I hope moving forward, but I can assure him what we've tried to produce today is the greatest possible certainty in a fairly uncertain world.

"And I can assure him that whilst I can't prevent issues from arising, where they arise, the government will seek to overcome them."