Saudi Arabia's PetroRabigh has extended maintenance work on its vacuum distillation unit (VDU) by a further six days, it said in a statement on Wednesday.

The firm, a joint venture between Saudi Aramco and Japan's Sumitomo Chemical, said last month the work was expected to last until May 10.

The financial impact of the maintenance was still being assessed and would be announced at a later date, it said.

Vacuum distillation, part of the refining process, helps to produce petroleum products from heavy oils left over from atmospheric distillation.  - Reuters