One fourth of the world's supertankers are sailing to China – the highest level since 2017, Bloomberg reports.

Most of the 109 China-bound supertankers are set to arrive in the country within the coming three months, taking place at the same time as the IMO 2020 sulfur regulations take effect. These regulations entail that the permitted sulfur content in marine fuel will be reduced from 3.5 percent to 0.5 percent.

"Following a deep and extended refinery maintenance season, refinery runs are rising significantly, especially with IMO 2020 only a few short months away," Jefferies LLC analyst Randy Giveans tells Bloomberg.

Giveans assesses that the many supertankers with itineraries set for China are an indication that the country is building up its oil inventories as a result of supply insecurity following the recent attack on a Saudi Arabian oil facility.

English Edit: Daniel Frank Christensen

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