June 24 (Reuters) - Africa Oil has agreed to buy out BTG Pactual Oil & Gas's 50% holding in their Prime Oil & Gas joint venture in a deal that will see it take on BTG as a major shareholder, it said on Monday.

Prime has offshore producing assets in Nigeria and accounts for 100% of Africa Oil's reserves and production. The deal is expected to be completed in the third quarter of 2025.

On completion BTG is expected to hold about 35% of Africa Oil's enlarged share capital, and to nominate Huw Jenkins as non-executive chair of the board and two other non-executive directors, Africa Oil said.

The agreement will "enhance our operations, deliver identifiable savings, and increase our capital returns to shareholders on a sustainable basis," said Africa Oil President and CEO Roger Tucker. (Reporting by Arunima Kumar and Deep Vakil in Bengaluru; Editing by Jan Harvey)