The work will encompass the 6-mile stretch of the route between Tomatin and Moy, the most northerly section of the programme.

Cabinet secretary for transport, infrastructure and connectivity, Michael Matheson, said: “The work to dual the A9 between Perth and Inverness is continuing at pace with draft Orders published for 95% of the route and construction of the second section to be dualled from Luncarty to Pass of Birnam about to start in the next few months following the intention to award announcement earlier this month.

“With the publication of the draft Orders for the Tomatin to Moy scheme in June this year, we are now able to award a ground investigation contract for the same scheme which will help inform ongoing design work.

“These vital investigations will start next month, with the work expected to last around 18 weeks.”

A Transport Scotland spokesperson said: “As some of this work will take place on or near the live carriageway and in order to ensure the safety of both road workers and road users we will need to introduce traffic management arrangements when required.

“Road users and local communities will be kept informed of our plans and we will endeavour to ensure that any disruption is kept to a minimum.”