Rolls-Royce is planning to release the first of its fleet of crewless ships by 2020.

The engineering giant is working with government-backed groups across northern Europe on the autonomous vessels.

The company estimates that the move could cut sea transport costs by as much as 20%.

Rolls-Royce vice president of innovation Oskar Levander said tugboats and ferries will be developed first, ahead of cargo vessels which will sail across international waters.

He said: "The development will start in a few countries, and these flag states will give the vessel permission to operate before we have international regulations in place."


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Major shipping firms are expected to adopt the technology in the hope it will boost profits.

However, unions have expressed concerns about the possible impact on sea-faring workers.

A spokesman for the international maritime union Nautilus said: "The pace of change is a challenge to safety and there are also many unanswered questions about the legal implications of the way in which operational and management responsibilities are being taken away from ships staff.

"We are concerned that technology is seen simply as a way to cut jobs and cut costs."

Autonomous ships also present challenges for insurers who have to consider the new types of risks that they will face.

Some analysts believe that with no crew to protect from piracy, autonomous ships will reduce demand for guards - an industry that has been booming in recent years.

International shipping expert Jonathan Moss, from law firm DWF, said: "The maritime industry as a whole may suffer in terms of employment levels.

"Similarly, these security guards have created a lot of opportunity for Lloyd's of London and bespoke insurance products that insure them."

Rolls-Royce maintains that crewless ships will be both safer than existing vessels and that they will lead to the creation of more jobs on land.

The company says it is embarking on major research projects in Britain and Singapore - and that it believes the development of autonomous ships will increase demand in areas such as cybersecurity.

A Bank of England study in 2015 suggested that up to 15 million jobs in the UK could eventually be lost to automation, with administrative, clerical and production roles most at risk.