Turquoise Hill Resources and Rio Tinto have entered into a binding Heads of Agreement (HoA) to provide an updated funding plan for the completion of the Oyu Tolgoi underground copper-gold project in Mongolia.

The funding plan is designed to address the estimated remaining funding requirement of around $2.3 billion and replaces the non-binding Memorandum of Understanding that Rio and Turquoise Hill previously entered into on September 9, 2020.

Under the HoA, subject to securing approval by Oyu Tolgoi LLC, the project joint venture, and any required support from the Government of Mongolia, Turquoise Hill and Rio Tinto will:

• Pursue re-profiling of existing project debt to better align with the revised mine plan, project timing and cash flows to reduce the currently projected funding requirements of OT by up to $1.4 billion; and
• Seek to raise up to $500 million in senior supplemental debt (SSD) under the existing project financing arrangements from selected international financial institutions.

In addition, Rio Tinto has committed to address any potential shortfalls from the re-profiling and additional SSD of up to $750 million by providing a senior co-lending facility on the same terms as Oyu Tolgoi’s project financing, while Turquoise Hill has committed to complete an equity offering of up to $500 million.

An updated feasibility study on the underground expansion at Oyu Tolgoi from June 2020 included a delay of 21 to 29 months for first sustainable production compared with the original 2016 feasibility study guidance and an increase of $1.3-$1.8 billion from the original $5.3 billion development capital. The process also saw 1.22 Mt of copper, 850,000 oz of gold and 7.01 Moz of silver removed from the Hugo Dummett North reserve base compared with the December 31, 2019 calculation, with some 80,000 t of copper, 70,000 oz of gold and 550,000 oz of silver added to the Hugo Dummett North Extension reserve base.

Since this announcement, Rio, Turquoise Hill and the Government of Mongolia have been trying to agree on a new funding pact for the sustainable development of the underground operation, which, in combination with open-pit mining, could produce around 500,000 t/y of copper at full capacity.

Steve Thibeault, Interim Chief Executive Officer of Turquoise Hill, said: “We are pleased to have reached a constructive and equitable agreement with Rio Tinto to fund the Oyu Tolgoi underground development. With a binding funding agreement now in place that sets out a process along a known timeline, we will be able to move ahead as expeditiously as possible with the development of the underground project at Oyu Tolgoi.

“We remain committed to continue delivering a benefit to all stakeholders, including Mongolia and its citizens, and to delivering significant long-term value for Turquoise Hill as this project progresses.”

Rio Tinto Copper Chief Executive Bold Baatar, added: “This agreement and alignment with Turquoise Hill represents a major milestone in the continued development of Oyu Tolgoi, which is expected to become one of the world’s largest copper mines and a significant contributor to the Mongolian economy for years to come. Commencing the re-profiling whilst concurrently listening, engaging and resolving the concerns of the Government of Mongolia are critical steps to maintaining momentum on the timely delivery of the Oyu Tolgoi Underground project.”

Following the HoA, Turquoise Hill and Rio have agreed to obtain an order dismissing the current arbitration on a “without prejudice basis” and without costs, including an order vacating the interim measures order, the companies said.