Former Rio Tinto chief executive Jean-Sebastien Jacques and several current Rio executives have been called to provide evidence to a Mongolian parliamentary inquiry into cost blowouts at the Oyu Tolgoi copper mine.
The mine is expected to be one of the world’s top-five producers of the red metal by the end of this decade but remains politically contentious in Mongolia after construction took almost two years longer than expected and cost almost $US1.7 billion more than planned.
Jean-Sebastien Jacques has had plenty of time to mess with the winning formula.  Bloomberg
The Mongolian government is a 34 per cent shareholder in the mine and was directly affected by the cost surges, while the schedule blowouts delayed the revenue that was expected from the project.
A parliamentary committee was established in September to investigate the blowouts and is scheduled to hold public hearings between December 8 and 12.
Close to 300 witnesses have been called by the inquiry, including several former Mongolian prime ministers and presidents, as well as Jacques, who was Rio chief executive between 2016 and 2020.
Before he became CEO, Jacques was Rio’s copper boss and struck a crucial agreement with the Mongolian government in 2015 to spend $US5.7 billion turning the small open-pit mine at Oyu Tolgoi into a giant underground mine.
That 2015 agreement ended a three-year impasse and was pivotal in Jacques being promoted to Rio CEO in early 2016.
Although Jacques could choose to ignore the invitation, the summons will be harder to ignore for current Rio staff, such as Brisbane-based Mongolian national Munkhsukh Sukhbaatar, Rio’s managing director for copper strategy and growth.
Another rising star at Rio, Chris Aitchison, has also been summoned to provide evidence.
Aitchison has spent the past three years working in Guinea helping to build the Simandou iron ore project. He is one of the favourites to be the next chief executive of the Mongolian company that owns the mine, Oyu Tolgoi LLC, with the incumbent Deirdre Lingenfelder set to step down on December 9.
The list of former Rio executives called to give evidence includes former copper boss Arnaud Soirat, former Oyu Tolgoi president and now Kincora Copper chairman Cameron McRae and former finance executive Luke Colton, who is now chief financial officer of Lithium Americas.
The inquiry is also keen to get evidence from Richard Bowley, the former Oyu Tolgoi employee who claimed in a United Kingdom court that Rio should have disclosed the cost and schedule blowouts to investors sooner.
Bowley told The Australian Financial Review he would decline the invitation to testify as he was disappointed by the limited scope of the inquiry.
Controversy over Oyu Tolgoi is nothing new for Rio, which was this year accused by the Mongolian government of being involved in political bribery in the UK High Court, as part of a claim designed to force Rio to produce more internal documents.
The High Court ruled that Rio did not have to produce the documents in an effective defeat for the Mongolian government.
A Rio spokesman confirmed the miner was aware of the hearings.
“Oyu Tolgoi and Rio Tinto acknowledge the parliamentary temporary oversight committee’s announcement regarding a hearing scheduled for early December 2025,” he said.
“We remain committed to constructive engagement with the committee and its inspectors and continue to provide requested information and documentation.”
Rio forgave $US2.4 billion of debt owed by the Mongolian government in 2022, but the parties continue to argue over tax and Mongolia is pushing for the interest rate on its remaining debts to be lowered.
“Negotiations between Rio Tinto and the government of Mongolia on the shareholder loan interest rate and the management agreement are ongoing,” said the Rio spokesman.
Mongolia forced the Oyu Tolgoi mine to make a significant engineering change in June, when it delayed approval for the mine to push into neighbouring tenements that are part-owned by Canadian company Entree Resources.

Published Date:2025-11-18