The company has signed up in China for two LNG-fuelled products tankers for delivery in 2016, with two options attached.

The 15,000-dwt vessels will come with Wartsila's new 5RT-flex 50 DF dual-fuel main engine and be built at Avic Dingheng.

"They are probably the world's cleanest ships," deputy chairman Tryggve Moller told the Sjofartstidningen daily.

He put the design's daily fuel consumption at less than 14 tons a day, compared to conventional vessels' use of between 22 tons and 25 tons.

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