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 WSJ.

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, according to Reuters.

PIF is Saudi Crown Prince Mohammed bin Salman’s vehicle to boost Saudi investments at home and abroad.