SINGAPORE: Saudi Arabia, the world’s largest oil exporter, is offering up to 400,000 tonnes of cracked fuel oil for sale from its joint venture refinery with Royal Dutch Shell in Jubail in May, traders said on Monday.

The residual fuel tender, which was issued by the state oil firm’s trading arm, Aramco Trading, closes on Wednesday with validity expiring on Thursday, traders said.

The cargoes are being offered from the 305,000 barrel per day (bpd) Saudi Aramco Shell Refinery Company (SASREF) in Jubail, traders said.

The cargo size for each parcel of 180-centistoke being offered is between 75,000-80,0000 tonnes, traders said.

The Saudi tender was issued just after buying interest emerged last week in tenders issued by Pakistan, Vietnam and South Korea.

Asia's fuel oil margins improved at the end of last week, with the front-month May crack shrinking 79 cents to a discount of $7.98 a barrel to Dubai crude, the narrowest since March 11, according to Reuters calculations.