Santander, Spain’s biggest bank, on Tuesday agreed to sell its 32.5 per cent stake in oil refiner Cepsa to the International Petroleum Investment Company (Ipic) of Abu Dhabi for about €2.8bn ($3.8bn).

The sale, following a year of intermittent negotiations, represents the divestment of the Spanish bank’s last remaining substantial equity holding. Unión Fenosa, the Spanish electricity group, will sell its 5 per cent stake in Cepsa as part of the same deal.