Talisman Energy is selling a 49 per cent interest in its UK division to Chinese firm Sinopec Corp. for $1.5 billion.
The Calgary-based company says the joint venture will focus on investment in the operating performance of the assets, including drilling and exploration opportunities.
Talisman says it will continue to handle operations, while Sinopec will be able to appoint staff to key positions.
"Collectively, we will invest more in the UK than Talisman would have on its own, leading to a stronger, more sustainable business," said Talisman president and CEO John Manzoni.
"We are reducing our working interest and capital spend in the UK business by approximately half, allowing us to focus on and fund growth areas within our portfolio. This brings our total divestment proceeds to approximately $2.5 billion so far this year."
Manzoni said the company plans to use about $500 million from the proceeds to buy back shares.
Talisman UK, based in Aberdeen, Scotland, has 564 full-time employees and about 1,950 contractors.
The transaction is expected to close by the end of the year, once the companies receive regulatory and government approval.