Saudi Aramco's Ras Tanura refinery, parts of which have been shut for maintenance since March, is expected to come back online in early May, three traders with knowledge of the plans said.

The planned maintenance at Ras Tanura, the Middle East's largest refinery with a crude processing capacity of 550,000 barrels per day (bpd), included the crude distillation unit (CDU), condensate splitter, hydrocracker and one of the three catalytic reformers, they said.

"The condensate splitter is expected to come back in April 30 and the hydrocracker will take another week or so," one trader said.

The CDU is already back online, two traders said. Aramco has been seeking gasoil and gasoline in the spot market since February to plug the supply shortage caused by the maintenance at a time when the demand is on the rise as summer approaches.

Saudi Arabia is the world's top oil exporter but it imports of gasoline and gasoil to meet booming fuel demand. - Reuters