As announced on 19 November 2018 Petrel Energy has agreed to acquire Warrego Energy through a reverse takeover, whereby Warrego shareholders will own approximately 77% of the enlarged Petrel, subject to shareholder approval at a general meeting on 31 January 2019. Following completion the enlarged company will be re-branded as Warrego Energy Ltd and will apply to list on the AIM exchange, targeted for 15 February 2019. Petrel holds WI in the Tesorillo and Ruedalabola exploration licences located in the Cadiz province, southern Spain through Tarba Energia, a joint venture between Petrel Energy (85%) and Prospex Oil & Gas (15%). Interests will be revised if Prospex executes an option to increase its share to 49.9% for EUR2 million (US$ 2.4 million). Tesorillo contains the Almarchal 1 (1965, Valdebro, 3,465m MD) gas discovery in Miocene Aljibe Formation sands, which is expected to be drilled by the Tesorillo 1 appraisal well during H2 2019. Ruedalabola contains the Puerto de Ojen 1 NFW which encountered gas shows in 1957. Aberdeen-based Warrego operates Australian North Perth Basin Exploration Permit EP469. 
Petrel Energy has agreed to acquire Warrego Energy through a reverse takeover, whereby Warrego shareholders will own approximately 77% of the enlarged Petrel, 