Saudi Arabia's sovereign wealth fund, the Public Investment Fund (PIF), has accumulated stakes worth about $1 billion in four major European oil companies, the Wall Street Journal reported on Wednesday, citing people familiar with the matter.

The four companies are Norway's Equinor ASA, Anglo-Dutch energy company Royal Dutch Shell, France's Total SA and Italy's Eni SPA, according to the newspaper.

The fund built a stake of about $200 million in Equinor in the days around a sharp rally in oil prices last week, the Journal reported, adding it could not learn the size of the stakes bought in the other three companies, but that the combined stakes were worth about $1 billion.

The purchase of the stakes comes during a downturn in the global oil and gas industry, as energy demand has slumped during the coronavirus outbreak.

A Saudi official cited by the Journal said that similar deals could take place in the future as well.

"The PIF is getting active again in the market..I would not be surprised if we see similar deals again," the official was quoted as having said by the newspaper.

PIF is Saudi Crown Prince Mohammed bin Salman's vehicle to boost Saudi investments at home and abroad, as he seeks to diversify the oil-heavy economy.

The fund manages over $300 billion in assets and has stakes in Uber and electric car company Lucid Motors.

It has also allocated $45 billion to SoftBank's $100 billion Vision Fund. On Monday, it disclosed an 8.2% stake in coronavirus-hit cruise operator Carnival Corp. 

None of the companies were immediately available for comment on the WSJ report.

(Reporting by Kanishka Singh in Bengaluru; Editing by Lincoln Feast and Muralikumar Anantharaman) ((Kanishka.Singh@thomsonreuters.com; +91 8061822801;))