Rolls-Royce is to slash one in six workers at its marine business as the oil price crash continues to hit the company.

The FTSE 100 group announced it would cut 800 of the division’s 4,800 staff as it “accelerated” the transformation of the company under chief executive Warren East.

The latest job cuts - which come on top of 1,000 announced last year - are expected to to deliver annual savings of between £45m and £50m a year from mid-2017, but deliver a £20m hit to the balance sheet in restructuring costs.

The bulk of the staff in the marine business - some 1,900 - are based in Norway, reflecting the division’s focus on supplying the offshore oil industry. A further 400 are employed in the UK, mainly in Bristol.

As well as producing and servicing naval engines and power systems, Rolls builds deckgear such as winches, and designs complex control systems to manoeuvre ships.

However, investment in new vessels and equipment by shipping companies has plunged as the oil price has collapsed to around $50 a barrel, from twice that level a few years ago, hitting Rolls’ marine operations.