Singapore-listed offshore shipbuilder and operator Otto Marine announced that its shipyard division has sold an anchor handling tug supply vessel (AHTS) to a third party for $100m, and will charter it back for eight years via its subsidiary GO Offshore.

The vessel, which is the fourth and final of the company's VS491 series, is currently under construction at Otto Marine's shipyard in Batam, Indonesia, and is expected to be delivered in the second quarter of 2015.

The deal is expected to make a positive contribution to the company’s balance sheet, said Otto Marine.