Saudi Aramco is in advanced talks for an all-stock deal to acquire a stake in Reliance Industries Ltd.’s oil refining and chemicals business, people with knowledge of the matter said.

The Saudi Arabian firm is discussing the purchase of a roughly 20% stake in the Reliance unit for about $20 billion to $25 billion-worth of Aramco shares, the people said, asking not to be identified because the information is private. Reliance, which is backed by Indian billionaire Mukesh Ambani, could reach an agreement with Aramco as soon as the coming weeks, the people said.

Shares in Reliance extended gains to as much as 2.6% in Mumbai after the Bloomberg News report.

A deal would forge closer ties between the world’s biggest oil exporter and one of the fastest-growing energy consumers.

It would seal more than two years of negotiations and mark Aramco’s first all-stock deal since its initial public offering in 2019. Ambani confirmed talks about a deal with an implied stake valuation of $15 billion that same year. Discussions were delayed by the onset of the coronavirus pandemic and slump in oil prices.

Energy markets have since recovered, with crude prices jumping around 35% this year to almost $70 a barrel. Aramco said last week due diligence on a deal with Reliance was underway.

A transaction would boost Aramco’s sales of crude to India. For Reliance, it would help to lock in a steady supply of oil for its giant refineries and make the Indian company a shareholder in Aramco. Based on Aramco’s market valuation of about $1.9 trillion, a transaction would give Reliance a stake of around 1%.

Details of the potential transaction are still being negotiated, and talks could drag on longer or fall apart, the people said. A representative for Aramco declined to comment. The Saudi government’s Center for International Communication didn’t immediately respond to an email requesting comment.

Saudi Goals

A representative for Reliance said the company does not have anything to add beyond Ambani’s comments at the shareholders’ meeting in June, when the conglomerate appointed Aramco Chairman Yasir Al-Rumayyan to the board. Ambani had said Reliance could finalize an investment deal with the oil producer this year.

The Saudi government sold 2% of Aramco in the IPO, raising almost $30 billion. It’s still the largest first-time share sale on record.

Crown Prince Mohammed bin Salman, the de facto ruler, said in April that the kingdom was in talks to sell a 1% stake in Aramco to a “leading global energy company.” He didn’t disclose which one.

“This deal could be very important in strengthening Aramco’s sales in the country where this company resides,” the prince had said.

Saudi Arabia shipped 613,000 barrels a day of crude to India in July, around 10% of its total exports.

The transaction would help Aramco reach its goal of more than doubling refining capacity to between 8 million and 10 million barrels of crude a day. The Saudi firm had 3.6 million barrels a day of capacity at the end of last year, including stakes in joint ventures.