Norway's Subsea 7 has clinched a "substantial" contract from Aker BP for the Aerfugl gas field development.

It will carry out 21km of tie-back work to the Skarv FPSO, 210km west of Sandnessjoen.

The contract also includes an option for Aerfugl phase 2.

Offshore operations will take place in 2019 and 2020.

Subsea 7 defines a substantial contract as being worth between $150m and $300m.