Bermuda-domiciled oil firm Gulf Keystone said chief executive Todd Kozel would retire next month, following a rocky period during which the company’s corporate governance and executive pay have been criticised.

Investors cheered the news as Gulf Keystone shares rocketed 14.75p, or 18.4 percent, in London Stock Exchange trading yesterday to close on 95p.

Mr Kozel will remain at the company he founded and at which he has been boss since 2001, in the role of executive director, conditional upon his re-election to the board by shareholders at Gulf Keystone’s annual general meeting on July 17.

The Texan, 47, was previously chairman and chief executive before coming under shareholder pressure to split the role, and to shake-up the company’s board.

Since then, Gulf Keystone has moved from London’s junior AIM market to the main list and Mr Kozel has seen his pay plunge from about $21 million to around $3 million.

Gulf Keystone’s prize asset is an oil field in the Kurdistan region of northern Iraq. The company said recently that its project were progressing despite escalating violence in the region.

The company also said in a statement that the two non-executives who joined its board last summer following the shareholder dispute, Jeremy Asher and John Bell, have ceased to be directors in line with its bye-laws.

Before yesterday’s rally, shares in Gulf Keystone have been hit this year by a significant downgrade in estimates of oil resources at its Shaikan field and a refinancing through a $250 million bond issue.