Repsol, S.A. (BME:REP) is in negotiations to sell a stake in its renewable energy unit, a move to help fund its strategic plan through 2027, according to four sources with knowledge of the talks. The company has received an unsolicited approach by an investor and has lined up Santander as advisor for the sale, the sources said. Repsol would keep more than 50% of the unit in a transaction that could involve the investor injecting new money into the business, the sources said.

Reuters was not able to establish the identity of the investor. Repsol and Santander declined to comment. Discussions were in the early stages, the sources added, cautioning there was no certainty that the deal would happen.

Repsol Renewables is valued at EUR 5.9 billion ($6.4 billion), including debt, according to a research note published by UBS in April.