A stretch of the A90 Aberdeen to Ellon road is to be upgraded to a dual carriageway.
But work on the route, between Balmedia and Tipperty, will not be able to begin until legal issues surrounding the proposed Aberdeen bypass are cleared up.
The Scottish Government has long come under pressure from local motorists to improve the bottleneck.
The project was highlighted in the SNP administration’s draft budget for 2011-12, announced last November. It stated that work on the new carriageway could progress when legal issues surrounding the Aberdeen Western Peripheral Route are resolved.
But pressure group Road Sense is challenging the 2009 decision to approve the 28-mile bypass after local objections and a four-month public inquiry.
Transport minister Keith Brown said: “The A90 is an important strategic route that carries traffic north of Aberdeen up to Fraserburgh. The local community have been pressing for the section between Balmedie and Tipperty to be dualled for a number of years.
“This scheme when completed will result in improved and more reliable journey times and improved safety for anyone using the A90 north of Aberdeen.”
He accepted some recommendations following an inquiry into the plans, but did not accept recommendations for fundamental redesign of sections of the route.
Brown continued: “I have therefore decided on the grounds of improving road safety and providing increased accessibility for local communities and the north-east in general, the orders for the dualling of the A90 between Balmedie and Tipperty should be made.”
Government agency Transport Scotland said the road is estimated to cost between £51M and £64M.
A spokesman for the agency added: “Assuming a successful outcome to the appeal against the AWPR, the cost estimates for both this scheme and the A90 Balmedie-Tipperty scheme will be reviewed and updated prior to the commencement of the formal procurement process.”