Dubai: Saudi Arabia’s Public Investment Fund (PIF) has selected Goldman Sachs & Co to advise on the sale of its stake in petrochemicals firm Sabic to state oil company Saudi Aramco, two sources familiar with the process told journalists on Monday.

Citigroup Inc won the mandate to advise Sabic on the transaction, the sources said.

Aramco plans to buy a controlling stake in Saudi Basic Industries Corp (Sabic), possibly taking the entire 70 percent holding owned by PIF, the kingdom’s sovereign wealth fund.

Goldman Sachs, the PIF and Sabic were not available for immediate comment. Citigroup declined to comment.

It is the kingdom’s biggest-ever M&A deal, intended to boost Aramco’s downstream business.

The sale will also provide a source of cash to the PIF after an initial public offering of Aramco was shelved.

Riyadh-listed Sabic, the world’s fourth largest petrochemicals company, has a market capitalisation of 385.2 billion Saudi riyals (Dh377.2 bilion or $103 billion).

Reuters previously reported that JPMorgan and Morgan Stanley were advising Aramco on the deal.