SMEC International will be contracted to conduct a feasibility study, an environmental impact assessment and prepare documents for requests for proposals from investors, cabinet spokesman minister Keheliya Rambukwelle said.
SMEC International is also the consultants to the Colombo - Katunayaka Expressway which is now under construction.
Phase one of the so-called Northern Expressway project from Colombo to Jaffna runs from just north of the capital to near Kandy in the Central Province via Kurunegala in the North Western province.
The first part of the Northern Expressway runs from Enderamulla, branching off from Colombo's outer circular highway and ends at Mirigama 42.5 kilometers later.
From Mirigama a 35 kilometer stretch of the expressway passes through Pothupitiya to Pellandeniya about 5 kilometers away from Kurunegala.
A 44 kilometer link expressway runs from Pothupitiya to within 9 kilometres of Katugastota town near Kandy near an existing road (A10) running from Kurunegala to Puttalam.
Treasury secretary P B Jayasundera said in May that at least serious bids have come from private investors in three countries to build the expressway which is estimated to cost 1.5 billion rupees.
The rest of the Northern Expressway involves connects to Jaffna. A connection is also expected to Trincomalee, where a port related industrial zone is planned.