Sovereign fund China Investment Corp is reviewing options for its 30 percent stake in French multinational electric utility Engie SA's exploration and production business, which it had bought for 2.3 billion euros in 2011.

According to people familiar with the matter, in July, the unit was seen having a potential to fetch about $4 billion.

The French utility, which operates in the fields of electricity generation and distribution, natural gas and renewable energy, is pushing ahead with a sale.

The $814-billion wealth fund has reached out to banks to seek pitches for a strategic review of its stake in the Engie business, which has assets spanning Europe and Africa, the people said.

CIC, based in Beijing, is unlikely to sell its holding and is leaning toward increasing it, the people said, asking not to be identified because the information is private.

Engie is planning to sell its upstream operations globally, including businesses in the United Kingdom, Norway, Algeria, Egypt, Germany and Asia, people familiar with the matter said in July.

The company has sent out marketing materials to potential bidders for the business, one person said this week.

The company hasn't yet received any formal bids, according to the person.

CIC signed an agreement with Engie in June 2015 agreeing to "reinforce" their investment cooperation, particularly in areas including renewable power, new technologies and energy efficiency. The sovereign fund hasn't made any final decision about what to do with its stake in the exploration business, the people said.

Bloomberg