Three companies have been shortlisted for a Scottish government contract to upgrade about five miles (8km) of the A9 as part of a delay-hit dualling project.

Balfour Beatty Civil Engineering Ltd, Wills Bros Civil Engineering Ltd and John Graham Construction Ltd have been invited to bid for the Tay Crossing to Ballinluig section in Perthshire.

Last month, Balfour Beatty was awarded a contract worth almost £185m to upgrade a six-mile (10km) stretch of the A9 between Tomatin and Moy south of Inverness.

In December, the Scottish government said the overall £3bn project to dual 77 miles (124km) of single carriageway between Inverness and Perth had been delayed by 10 years to 2035.

During a site visit to Tomatin, Transport Secretary Fiona Hyslop said the latest contract announcement demonstrated the government’s commitment to progressing the improvements.

She said: “Shortlisting contractors for the Tay Crossing to Ballinluig project is the next step in the procurement process and we expect to award this contract in summer 2025.”

The Scottish government was forced to retender the work for the Tomatin to Moy section last year after only one contractor showed interest in the job.

Ms Hyslop said she had seen for herself the “complex nature” of the construction contract.

“When construction gets underway in earnest on this section, it will roll continually until the A9 between Perth and Inverness is fully dualled.

“The Tay Crossing to Ballinluig project will be the next section to reach construction,” she added.

Expected completion dates of the remaining sections, subject to contract and funding processes, are:

Tomatin to Moy – by the end of 2027

Tay Crossing to Ballinluig – by the end of 2028

Pitlochry to Killiecrankie – by the end of 2030

Pass of Birnam to Tay Crossing – by the end of 2032

A9 North (Crubenmore to Kincraig and Dalraddy to Slochd) – by end of 2033 at the earliest

A9 Central (Killiecrankie to Glen Garry, Glen Garry to Dalwhinnie and Dalwhinnie to Crubenmore) – by end of 2035 at the earliest