Saudi Aramco (TADAWUL:2222) increased supplies of vacuum gas oil for export from the Jazan refinery (TADAWUL:6090) in May, according to dealers and shipping data, in a sign that the refinery has not yet reached its full production capacity.

The Jizan refinery, Aramco's newest refinery, was expected to increase its production of diesel containing 10 parts per million sulfur and reduce its exports of vacuum gas oil during the current quarter when it reaches full capacity.

But shipping sector data showed that Aramco recently offered three cargoes of 525,000 barrels each of vacuum gas oil for loading from the Jazan refinery in May, up from just two cargoes in April.

Saudi Aramco could not be immediately reached for comment.

Shipments are likely to be loaded between May 1-3 and May 11-13 and May 21-23. Aramco usually releases up to two shipments of vacuum gas oil per month, according to industry sources and previous bidding data.

Vacuum gas oil, an oily residue left over from the petroleum distillation process, is used as a feedstock for refineries to produce diesel.