Vancouver-based Turquoise Hill Resources announced on Thursday that Ulf Quellman had resigned as CEO, having agreed with the board that it would not be in the best interest of the company for him to continue in his position.
Majority shareholder Rio Tinto reportedly felt that new leadership was needed to advance work on matters related to the Oyu Tolgoi project, in Mongolia.
Rio Tinto has indicated that it will not vote in favour of Quellmann’s election as director at the company’s annual general meeting in May, Turquoise Hill said in a statement.
A dispute between Rio Tinto and Turquoise Hill over funding the Oyu Tolgoi project has spilled into the open in recent months.Costs for the expansion have ballooned to $6.75-billion, about $1.4-billion more than Rio Tinto's estimate in 2016.
The company appointed former CFO Steve Thibeault as interim CEO to progress the Oyu Tolgoi funding plan and oversee day-to-day operations of the organisation.
Thibeault served as the CFO between June 2014 and April 2017 and has since not had any affiliation with either Turquoise Hill or Rio Tinto.
He led the negotiations of the funding agreements for Turquoise Hill that the company entered into with Rio Tinto in 2015.
Shares in Turquoise Hill closed at C$17.96 apiece, down 9%, giving the company a market capitalisation of C$3.6-billion.
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