Eight companies have been shortlisted to bid for three large design contracts in Scotland, each worth £40-£60, under the A9 Dualling Programme.

The shortlisted bidders are AECOM / Mott MacDonald, Arup, Atkins / Mouchel, Capita, CH2M Hill / Fairhurst, Jacobs, URS and WSP / Ramboll / Fehily Timoney.

The successful bidders will be provided with steady work over the next 12 years on the contracts, which will also offer several opportunities for small and medium firms through sub-consultancy work.

Invitations to tender for the contracts are expected to be called next month.

Transport Minister Keith Brown said that the A9 Dualling Programme is the most expensive transport project in Scotland’s history and presents some of the most challenging work ever witnessed.

"The A9 Dualling Programme is the most expensive transport project in Scotland’s history and presents some of the most challenging work ever witnessed."

"The strength and expertise of these bidders, including some of the UK’s biggest design consultancies, is testament to the recognition that this ambitious project has in the engineering consultancy market," the minister noted.

The £3bn A9 project involves the upgrade of 80 miles of single carriageway along the route between the cities of Perth and Inverness.

The proposed dualling is vital for society as it improves road safety, journey times and reliability, along with improving economic growth.

Half of the dualling project is scheduled to be completed by 2022.

"There are many challenges along this route, which passes through areas that are hugely important in terms of Scotland’s wildlife and landscape."

"The publication of the contract notice for GI works on this section next month will start the tender process for these important ground investigations, which will give us the detailed information needed to take forward the scheme," Brown said.