DUBAI: Saudi Arabia’s $620 billion sovereign wealth fund is expected to tap international debt markets for a debut green bonds issue as soon as next week, five sources familiar with the matter told Reuters.

The Public Investment Fund is at the center of Saudi Arabia’s ambitious reform plans being spearheaded by Crown Prince Mohammed bin Salman to wean the economy off oil.

The crown prince said in December that it would invest about $40 billion in the local economy this year, after spending about $22 billion last year.

Reuters reported in July last year that PIF was setting up a financing framework that would allow it to raise green bonds.

PIF in February announced a green finance framework that showed net proceeds from a debt sale would go toward eligible projects, including in renewable energy, clean transport and green buildings.

PIF has been monitoring the market for months to find a window to issue, three sources said, amid enduring volatility that has rattled markets for much of this year as central banks use aggressive tightening to try to tame decades-high inflation.

That window could come as soon as next week, depending on market conditions, or possibly in October, two of the sources said.

PIF declined to comment.

The deal is expected to raise billions of dollars, sources have said.

Fitch Ratings and Moody’s in February assigned PIF an ‘A’ and ‘A1’ credit rating, respectively.

The banks on the deal are expected to be ones that have lent to PIF, two sources said.

PIF started raising bank debt in 2018 with an $11 billion facility, followed in 2019 by a $10 billion loan which it then repaid in 2020.

Those loans were provided by what PIF has called its core banking group comprising Bank of America, BNP Paribas , Citi, Credit Agricole, HSBC, JPMorgan, Mizuho, MUFG, Standard Chartered and SMBC.

In March last year, the wealth fund raised $15 billion from 17 banks comprising most of the core banking group as well as Credit Suisse, Deutsche Bank, First Abu Dhabi Bank, Goldman Sachs, Intesa Sanpaolo , Morgan Stanley, Natixis and Societe Generale .