Italian energy company Eni will sell a 30% stake in its giant Egyptian offshore gas field Zohr to Russia’s Rosneft for $1.575 billion, pressing ahead with asset sales to fund investments and offset weak oil prices.

Eni, which owns 90% of the Shorouk concession containing Zohr, said Rosneft would pay $1.125 billion cash for the stake and would reimburse investments already carried out by Eni for around $450 million.

The deal comes less than a month after Eni's sale of a 10% stake in Zohr to BP at the same implied price, bringing overall proceeds to around $2.1 billion.

Eni, whose cash flow fell 19% in the third quarter due to low oil prices, pledged at the start of the year to sell 7 billion euros ($7.43 billion) worth of assets to 2019—5 billion euros in the first two years.

“This is a great success for Eni to receive $2.1 billion for a year’s work and have major partners to share the risk and capex,” Bernstein oil analyst Oswald Clint said.

At 1354 GMT Eni shares were up 4.2% while the European oil and gas index was up 2.1%.

Oil prices rose as much as 6.5% on Dec. 12 after OPEC and some of its rivals reached their first deal since 2001 to jointly reduce output, though are still well below values above $100 a barrel seen in 2014.

Selling down stakes in oil and gas fields it operates is part of Eni's so-called "dual exploration" strategy to raise cash to fund development and support dividends. In the last four years, Eni has raised about $6.3 billion in this way.

Zohr, discovered by Eni in 2015, is the biggest gas field in the Mediterranean with an estimated 850 billion cubic meters of gas in place.

The approval process for development of the field was completed in February and first gas should be produced by the end of 2017.

In November, Eni Chief Executive Claudio Descalzi said he wanted to cut Eni’s stake in Zohr to 50%.

Rosneft, like BP, has an option to buy a further 5% stake.

“We suspect BP and Rosneft will take the additional 5% next year given the high return of this field,” Bernstein’s Clint said.

($1 = 0.9426 euros)

Offshore