Imperial Oil said on Thursday that CEO Brad Corson will retire, with John Whelan, currently ExxonMobil Canada's upstream senior vice president, taking his place on May 8.

Imperial Oil has tapped company veteran John Whelan to take over from Chairman, President and Chief Executive Brad Corson when he retires this spring after roughly five years running the Canadian oil-and-gas producer.

Imperial Oil (NYSE:IMO) said Thursday that CEO Brad Corson will retire, with John Whelan, currently Exxon Mobil Canada's upstream senior VP, succeeding him effective May 8. The Exxon-controlled (XOM) company will appoint Whelan as president starting April 1 as part of the succession process,