Portugal's Galp is putting up for sale 40% of its stake in the exploration block off Namibia, where it recently made a major oil discovery.

According to the international press, the information was provided by anonymous sources who were not authorized to speak to the media.

Galp holds a stake of 80% and is the operator of Petroleum Exploration License 83, which covers an area of almost ten thousand square kilometers in the Orange Basin. NAMCOR and Custos hold 10% each.

The block includes the Mopane field, which Galp estimates will contain at least ten billion barrels of oil and gas after the conclusion of the first exploration phase.

The company had previously indicated that it might launch a process to attract other investors to its projects in Namibia, as these could reach a large scale.

Galp is also offering to cede control of the project's development to the potential buyer, which is expected to be a major international rival with a strong track record in project management.

Galp has hired Bank of America to manage the sale process, which could raise several billion dollars for Galp, although the exact amount has not yet been revealed.

Galp has several minority positions in the holdings offshore in the oil and gas sector where it is present - in Brazil and Mozambique - but is not an operator in any of these blocks. Namibia could become a new source of revenue for the company.