The move, part of a campaign to open up the oil-rich kingdom’s economy, follows a transfer last year of 4% of Aramco shares, estimated at the time to be worth US$80 billion.

Authorities did not give a value for the latest shares, which have been moved from the world’s biggest oil exporter to Sanabil Investments, a firm controlled by the Public Investment Fund (PIF) that is led by Crown Prince Mohammed bin Salman, Saudi Press Agency said.

The prince, Saudi Arabia’s de facto ruler, billed the move as part of a push “to boost and diversify the national economy and expand investment opportunities”, according to the report.

The shares of the mostly state-owned oil giant moved last year went directly to the PIF, one of the world’s biggest sovereign wealth funds with more than US$620 billion in assets.

Prince Mohammed said the latest transfer will “solidify PIF’s strong financial position”.

He also stressed that the state “will remain Saudi Aramco’s largest shareholder following the transfer, with total ownership of (90.18%) of the company’s shares,” the report said.