Mongolia is scheduled to launch a series of public hearings next week to examine the Oyu Tolgoi copper and gold mine, a project projected to become one of the world’s top copper producers, as lawmakers question whether the country is receiving its fair share of its profits.

The Parliamentary Oversight Committee on Oyu Tolgoi, established earlier this year under a legislative resolution, is investigating whether the state has benefitted adequately from the multibillion-dollar mine.

The mine’s initial open-pit development and surface facilities carried a price tag of about $6.4bn, while the ongoing underground expansion, expected to drive most of its future output, has been budgeted at more than $7bn.

Lawmakers say the hearings will focus on resource valuations, licensing decisions and the financing structure behind the underground build-out. 

A key point for lawmakers is how Mongolia will benefit from the resources within Entrée LLC’s concession areas, including the Javkhlant and Shivee Tolgoi licences. The licences are registered to Entrée LLC, a Mongolian subsidiary of Entrée Resources, though they are managed as part of the Oyu Tolgoi joint venture.

Oyu Tolgoi LLC, the project’s operator and a majority-owned subsidiary of Anglo-Australian mining giant Rio Tinto, has faced heightened scrutiny in recent months. The company launched an internal investigation into alleged procurement irregularities earlier this year, prompting lawmakers to increase oversight. Company officials say they are cooperating with information requests but have raised concerns about security issues surrounding the committee’s proceedings.

Up to 300 witnesses, including former prime ministers, senior mining officials and industry executives, are expected to be called during the hearings. Parliamentary leaders say the testimony will help determine whether past agreements and financing terms, including shareholder loans used to fund the underground mine, should be renegotiated.

Batnairamdal Otgonshar, chair of the oversight committee, says he has faced heightened pressure in recent weeks, reporting to authorities that he has been followed by unmarked vehicles.

“This act not only infringes upon my individual rights but also undermines the immunity and integrity of Parliament and attempts to interfere with an official parliamentary oversight process,” Batnairamdal said in an email to bne IntelliNews. “The matter has been formally referred to the relevant law-enforcement bodies.”

In addition to the licence review, Batnairamdal said another focus is the shareholders’ agreement, which outlines the project’s financing. He said it includes a $12bn loan from Rio Tinto to Oyu Tolgoi LLC with an interest rate of 11.3%.

“This high loan interest means that by the time the principal is repaid, cumulative interest costs could exceed the borrowed amount — delaying Mongolia’s share of profits, or dividends, until the 2030s or even 2040s,” Batnairamdal said.

The agreement allows the interest rate to be renegotiated every seven years.

“If we miss this opportunity, we lose the chance to renegotiate for another seven years,” he said.

“Our oversight committee will push for the government to act now to reduce the interest rate, in line with international standards. This is a matter of national economic security and falls squarely within our committee’s mandate,” Batnairamdal said.

The Oyu Tolgoi project has long been a source of political debate in Mongolia, where many citizens see the mine as essential to national growth but worry the country has not captured enough of its value. The underground expansion is expected to boost Oyu Tolgoi into the ranks of the world’s top copper producers amid rising global demand for the metal.

Rio Tinto did not immediately respond to questions from bne IntelliNews related to the upcoming hearings and the possibility that Mongolia might seek new investment terms.  

The committee’s findings, expected in early 2026, could shape future investment in Mongolia’s mining sector and influence the government’s relationship with one of its largest foreign partners.