Saudi Arabia's Public Investment Fund (PIF) is in talks with banks to raise a short-term bridge loan for as much as $8 billion to use for new investments, two sources said.

The sovereign wealth fund finalized a deal last month to sell its 70 percent stake in Saudi Basic Industries (Sabic) to Saudi Aramco for $69.1 billion.

Proceeds from the Sabic deal, which Saudi Aramco has said is expected to close in 2020, could take a few months to come through to PIF, while a document seen by Reuters said the oil giant will pay for the deal in tranches.

One of the sources said the $5 to $8 billion loan, which could be for a period of less than one year, will be repaid from the proceeds PIF gets from selling its Sabic stake.

A PIF spokesman did not comment on the details of the loan, but said in an email that raising debt is part of its strategy.

"As outlined in the PIF Program, the long-term funding strategy includes four sources of finance, including capital injections and asset transfers by the government, retained investment returns, and loans and debt instruments."

Banks are likely to underwrite the bridge loan, which was earlier reported by Bloomberg, as part of the deal, the second source said.

Last year PIF took out an $11 billion international syndicated loan, its first commercial borrowing.

The first loan was provided by JP Morgan, Citigroup, HSBC, BNP Paribas, Standard Chartered, Bank of China, Industrial and Commercial Bank of China, Goldman Sachs, Morgan Stanley, SMBC, Mizuho, MUFG, Credit Agricole, Societe Generale and Bank of America Merrill Lynch, IFR reported.

PIF has been given the task of helping to deliver the so-called Vision 2030 reform plan, an ambitious economic program announced by the government in 2016 designed to free the kingdom from dependence on oil exports.

The fund has also made substantial commitments to technology companies or investments, including a $45 billion agreement to invest in a giant tech fund led by Japan's Softbank.

It has also committed $20 billion to an infrastructure fund planned by Blackstone Group.