American oil giant, Chevron is concluding plans to sell several Nigerian oilfields as part of a global drive to reshape its portfolio as it focuses on growing its U.S. shale output, banking and industry sources said.

Chevron in this move is joining rivals including Exxon Mobil and Royal Dutch Shell in a drive by foreign oil companies to reduce their footprint in Nigeria which has been mired in political and security instability in recent years.

The San Ramon, California-based company, Nigeria’s third largest oil producer, is looking for buyers for a number of its the onshore and shallow offshore fields, where local producers have expanded their presence.

Reuters reports that Chevron did not respond to a request for comment.

Chevron’s Nigerian subsidiary operates and holds a 40 per cent interest in 8 blocks in the onshore and near-onshore regions of the Niger Delta under a joint venture with Nigeria’s National Petroleum Company (NNPC), according to its website.

The discussions are being held directly with potential buyers and Chevron is not planning to launch a tender process for the assets at this stage, two of the sources said.