A joint venture of Cowi and Multiconsult will design the new line, which run underground from Oslo’s transport hub, Majorstuen, west to the peninsula.
The project includes six new stations, the metro tunnel and the design of the underground maintenance centre in Fornebu. The Fornebu peninsula was formerly the site of Oslo’s international airport and has since been redeveloped into a mixed residential and business district.
Cowi CEO Lars-Peter Søbye said: "We are proud to be designing this exciting and hugely important project. As well as the classic tunnel engineering competencies, we will also be consulting on issues related to water and the environment."
The government's latest National Transport Plan calls for construction of the new line to begin in 2021 and complete in 2025.