Rio Tinto has entered into binding agreements with Chile’s state-owned mining company Codelco to form a joint venture for the development of the Salar de Maricunga lithium project. The Anglo-Australian mining giant will invest up to $900 million in the initiative, which aims to extract lithium from one of the highest-grade brine deposits globally, located in Chile’s Atacama region.

Under the agreement, Rio Tinto will acquire a 49.99% interest in Salar de Maricunga SpA, the entity that holds Codelco’s mining concessions and licenses for the project. The company will contribute an initial $350 million to fund technical studies and advance the project to a final investment decision. If approved, Rio Tinto will invest an additional $500 million for construction, with a further $50 million contingent on the project delivering its first lithium by the end of 2030.

The deal, expected to close by the first quarter of 2026, remains subject to regulatory approvals and standard closing conditions.

“This partnership reflects our commitment to critical minerals and sustainable development,” said Rio Tinto Chief Executive Jakob Stausholm. “We are honored to join Codelco in advancing a world-class lithium resource using Direct Lithium Extraction technology. This project will support our strategy of growing our lithium portfolio to meet rising global demand for energy transition materials.”

Stausholm added that the JV builds on Rio Tinto’s existing copper partnerships with Codelco in Chile and emphasized the company’s intention to deliver long-term benefits to the Atacama region, including shared infrastructure and strategies to reduce water usage.

The joint venture will prioritize updating mineral resource estimates and conducting further feasibility studies. Both companies will fund development in proportion to their ownership and collaborate on initiatives aimed at community engagement, infrastructure development, and environmentally responsible mining practices.

Codelco Chairman Máximo Pacheco praised the alliance, calling Rio Tinto the most attractive partner for both the company and Chile. “This joint venture supports our broader lithium diversification strategy, which is crucial for the energy transition,” Pacheco said. “We are proud to work with a company of Rio Tinto’s stature on a project that is vital to Chile’s future.”

This move follows Rio Tinto’s announcement in January 2025 to launch a dedicated lithium division, shortly after completing its $6.7 billion acquisition of Arcadium Lithium. The company continues to expand its presence in critical minerals to meet the increasing global demand driven by electrification and clean energy technologies.