(Sharecast News) - Infrastructure solutions company Costain has been appointed to deliver "major improvements" on the A19 road for Highways England, it announced on Friday, as part of the government-owned company's 'Regional Investment Programme'.The London-listed firm said it had already been working with Highways England and local stakeholders to develop the design and delivery strategy for the £125m upgrade scheme.It said the improvements at Testos roundabout would relieve severe congestion, and reduce journey times.The roundabout was described as a major junction, linking the north-south A19 corridor with the strategic eastern route around the busy Tyneside conurbation.Following development consent for the project, which was granted by the Secretary of State for Transport in September last year, construction work was expected to begin "imminently".Costain said that in partnership with Highways England, it was also developing a scheme to improve the adjacent junction at Downhill Lane.Construction there would be integrated into the Testos improvements.The A19 appointment followed Costain's six-year Regional Investment Programme framework contract award by Highways England, as 'Delivery Integration Partner' in the North region and in the East region, which was announced in November last year.Although not part of that framework, the company said the A19 improvements were a "timely precursor" to other major highway schemes planned in the north east under the programme."I am delighted that we are at the forefront of helping Highways England deliver its ambitious Regional Investment Programme, which will significantly enhance network capacity, improving the lives of local people and supporting broad-based economic growth," said Costain chief executive officer Andrew Wyllie.