Rolls-Royce has arranged a sale of its commercial marine business to Norwegian group Kongsberg.

The UK manufacturer says the segment has an enterprise value of £500 million ($662 million) and will generate net proceeds of £350-400 million, taking account of pension liabilities, separation cost, adviser fees and working capital.

R-R chief executive Warren East states that the sale will "enable us to focus on our three core businesses" – aerospace, defence and power systems.

The commercial marine division employs around 3,600 staff members – the majority of whom are located in the Nordic region. It generated a £70 million operating loss on revenue worth £817 million in 2017, R-R says.

In June, the manufacturer disclosed plans to make 4,600 positions redundant across the group by 2020.

It says the commercial marine segment and Kongsberg's business are complementary and that the Norwegian group will be a partner for R-R's defence division.

R-R unit Bergen Engines will remain a part of the group's power systems division, while naval gas turbine activities will continue within the manufacturer's defence segment.

The power systems division will "continue to supply MTU engines to a range of customers in the marine market", R-R says.

It notes that the deal has been approved by both its and Kongsberg's boards and is to be completed during the first of quarter 2019, pending regulatory approval.

R-R asserts that the sale will provide "additional capital to judiciously pursue opportunities that will drive greater returns for the group".