The completion of PetroRabigh’s Phase II expansion will be delayed by nine months, raising the cost and forcing the Saudia Arabian petrochemical producer and refiner to seek more cash from shareholders, it said.

The delay to September 2016 is the latest issue to hit the project, which will let the company manufacture higher margin products but has faced a number of uncertainties since it was proposed in 2009, mostly over the cost of the huge expansion.

The total cost will now be SR31 billion ($8.3 billion), SR1 billion more than the previous figure, according to a bourse filing from the firm, which is a joint venture between Saudi Aramco and Sumitomo Chemical.

PetroRabigh blamed the increase on “the failure of the key contractors of the project to meet the planned implementation schedule”, without elaborating. The delay also means that a planned rights issue to support the funding costs will need to rise to SR9.26 billion, SR2.24 billion more than initially announced in April, the company said in a separate bourse filing.

PetroRabigh has already signed loans worth SR19.4 billion to finance the project, with a significant chunk coming from the Japan Bank for International Cooperation and the state-owned Public Investment Fund.