Rio Tinto's acquisition of the Turquoise Hill mine has been suspended indefinitely due to personnel corruption.
The Oyu Tolgoi underground mine is a critical development project in Rio. Rio Tinto Group subsidiary Oyu Tolgoi LLC is conducting an internal investigation into allegations of corruption and unethical behavior in Mongolia and has sought assistance from law enforcement.
“We are aware of procurement activities, and we are conducting a comprehensive internal investigation and have also sought the assistance of law enforcement agencies."
Rio owns a 66% stake in Oyu Tolgoi LLC and is developing an underground deposit that plans to become the fourth largest copper mine in the world by 2030. The rest belongs to the Mongolian government. The field is one of Rio Tinto's largest and most valuable assets, and although production rose 78% in the last quarter, its development has been marred by political instability, cost overruns and delays. Rio Tinto (ASX, LSE: RIO) has agreed to pay nearly $139 million this year to settle a long-running class action accusing it of covering up delays in the development of a $7 billion copper mine in Mongolia. Rio entered into a settlement in the summer of 2025 to "avoid the uncertainty and costs associated with continuing litigation."
