Ophir Energy has agreed to acquire the interests in seven deepwater production-sharing contracts (PSCs) in Indonesia from Niko Resources.
The company will pay $31m, with further payments of approximately $56m depending on the success of future exploration.
The seven fields, spanning 21,500km², hold prospective resources of over 3 billion barrels of oil equivalent.
Upon completion of the deal, Ophir will operate six of the seven fields and increase its total exploration acreage by 40%.
Norway-based Statoil and Italian energy firm Eni will serve as partners.
The licences are divided into three areas, which include West Papua, Western Birds Head and the Makassar Strait.
Ophir said the acquired acreage has already seen some 3D seismic acquisition and the maturing of various leads and prospects.
The initial focus of activity will be to reinterpret the current 3D seismic data and commission new 3D surveys on various blocks.
Initial drilling campaigns are expected to commence in early 2016, although Ophir has the option to reduce its cost exposure to some of the wells before drilling.
The transaction is subject to approval by SKKMiGas and the Indonesia Government.
Ophir Energy CEO Nick Cooper said: "We are excited by the exploration and market opportunities in South East Asia, which can complement our continued expansion in Africa.
"This transaction with Niko Resources provides one new country entry, but access to three new core areas. The asset package adds a high impact, deepwater, exploration portfolio to our existing asset base at a very low entry cost."
Niko Resources chairman and interim chief executive officer Kevin Clarke said: "The sale of these PSCs aligns with our strategy to strengthening our balance sheet, while maintaining exposure to future potential exploration success."