The £34m-£38m contract is the second win for the duo in the last month following success on Cumbria’s £80m Thirlmere water mains project.

The joint venture beat rival bids from Balfour Beatty, Interserve, and John Paul Construction/Somaque Engenharia.

Under the Scottish deal, which is subject to the mandatory 10 day standstill period, the pairing will build a 4km bypass.

This will consist of two roundabouts, at Hillend and Highfield, and a viaduct to enable road users to travel over the River Garnock and the Glasgow to Ayr railway line.

Works are also required to connect the new Bypass to the existing A737 Trunk Road east of Highfield.

Transport Minister Humza Yousaf said: “Over the past few months, preparatory works have been undertaken on the site including archaeological investigations, fencing and vegetation clearance.

“The award of this contract, subject to the mandatory standstill period, enables the main works contractor to finalise its designs and establish a base on site before it can begin the main construction works in the coming weeks.”