The US firm, Cobalt International Energy Inc, announced that the proposed $1.75b sale of a 40% stake in two offshore oil blocks in Angola to the state oil company, Sonangol, has automatically ended, after failing to obtain government approvals within the last 12-months, Reuters reported.

Cobalt Angola and Sonangol signed the purchase and sale agreement in August 2015, with Sonangol paying $250m. The closing of the deal was subjected to the approval of the Angolan government, which was not obtained during the assigned timeframe. Currently, the two companies are working together to understand and agree on the financial and operational implications of the termination, according to Offshore Post.

Cobalt’s shares tumbled more than 40% early August when the company first said that the deal was unlikely to close.