Engine manufacturer MAN Diesel & Turbo has taken the unusual step of offering an discount to the first 10 customers that are prepared to sign up to have their vessel's propulsion system switched from heavy fuel oil (HFO) to gas.

MAN chief sales officer Wayne Jones made the offer at the "Our Ocean 2017 Conference" in Malta on Friday.

He told delegates: "In order to encourage more ship owners to follow this example, MAN Diesel & Turbo is pledging a total of EUR 2m ($2.35m)