Galp Energia, SGPS, S.A. (ENXTLS:GALP) has launched the sale of half of its stake in an exploration block offshore Namibia where it has made a major oil discovery, three industry sources familiar with the matter told Reuters. Galp's Mopane discovery, which is estimated to hold at least 10 billion barrels of oil and gas equivalent, appears to be one of the largest in the basin which could help kickstart the southern African country's oil industry even as governments around the world seek to reduce fossil fuel consumption. Galp has an 80% stake in Petroleum Exploration Licence 83 (PEL 83), which covers almost 10,000 square kilometres (3,860 square miles) in the Orange Basin, with Namibia's national oil company NAMCOR and independent exploration group Custos each holding another 10%.

Lisbon-based Galp is offering to sell half of its stake in the block, said the sources, who could not be named because they are not authorised to speak to the media. It is also offering to cede control of the development of the project to the potential buyer, expected to be a major international rival with a strong track record in project management, the sources said. Galp declined to comment.

It has previously indicated it could launch a process to raise capital for the development of its projects in Namibia, as they could reach a large scale. It has hired Bank of America to run the sale process, which could raise several billion dollars for Galp, although the exact value is unclear, the sources said. Bank of America declined to comment.

Galp shares closed over 20% higher following Galp's update on the Mopane field and Reuters reporting the sale process.