Argentina and Chile Press Their Cross-Border Mining Treaty at Santiago Summit

ARGENTINA · CHILE · MINING

Chile convened the region’s mining ministers in Santiago this week and used the moment to press its 1997 mining treaty with Argentina, a pact it says could unlock US$20.7 billion in cross-border copper investment.

What happened in Santiago this week

On Thursday 27 August 2026, officials from Argentina and Chile sat down under the Mining Integration and Complementation Treaty. The focus was the technical review of projects that could benefit from the pact.

The same day, Chile’s National Mining Society, known as SONAMI, opened its Cumbre de la Minería 2026 at Santiago’s Metropolitan events centre. President José Antonio Kast and SONAMI president Jorge Riesco opened the gathering.

Argentina’s mining secretary, Luis Enrique Lucero, was the most watched foreign guest. He shared a panel with the vice ministers of Bolivia, Ecuador and the Dominican Republic, with Canadian representatives also in the room.

The panel asked a blunt question. Can Latin America coordinate on critical minerals instead of competing country by country for the same investment?

Local media also reported that Argentina and Chile approved protocols for operating mining projects in the border zone. That step gives the revived treaty its first operational teeth.

A 1997 treaty with a modern purpose

The mining treaty was signed in 1997, an era when cross-border projects were rare. It lets companies work deposits on the frontier as if both countries were one, through project-specific protocols.

Those protocols coordinate customs, taxation, infrastructure, permits and labour rules. Without them, a mine that straddles the Andes faces two full sets of paperwork.

The treaty lay mostly dormant for decades. Chile’s Economy and Mining Minister Daniel Mas and Argentina’s Lucero agreed in April to revive it, and its administrative commission met again in Buenos Aires on 7 July.

Chile has also staffed the mechanism. During Cesco Week 2026 it ratified Rodrigo Urquiza, the international affairs chief of its copper commission Cochilco, as the commission’s executive secretary for Chile.

The original showcase was Pascua-Lama, the binational gold and silver project that Barrick Gold eventually abandoned. The ghost of that failure still shapes the environmental debate on both sides.

The money behind the diplomacy

Chile’s Mining Ministry puts the prize at more than US$20.7 billion in unlocked investment. It also projects 540,000 tonnes of additional copper production a year.

The logic is simple geography. Argentine projects near the Andes could reach Chilean Pacific ports and Chilean infrastructure, cutting costs and transport time.

Chile brings the scale of a mining superpower to that bargain. According to United States Geological Survey figures released by SONAMI, Chile produces 23 percent of the world’s copper and holds 18 percent of its reserves.

Argentina brings the untapped ground. It has produced no copper since the Bajo de la Alumbrera mine closed in 2018, yet analysts say its project pipeline could make it a top-ten world producer by 2030.

Joaquín Villarino, head of Chile’s Mining Council, framed the benefit for his side. Binational projects, he said, open enormous opportunities for Chilean suppliers, infrastructure and services.

The three projects at the front of the queue

Representatives of three projects met in Santiago on Friday 28 August for a mining integration seminar. They are Los Azules, El Pachón and Vicuña.

Los Azules, in San Juan province, belongs to McEwen Copper and sits close to the Chilean border. Its owner says it does not plan to use Chilean ports, but it is following the talks closely.

El Pachón is Glencore’s copper project, also on the Argentine side. Vicuña, the joint venture of Lundin Mining and BHP, is the true cross-border giant, with total investment estimated near US$18 billion.

Vicuña has said it plans to use desalinated Pacific water, without confirming Chilean infrastructure. BHP has not said whether it would use existing Chilean installations.

The environmental fight that never went away

The treaty revival has alarmed scientists and environmental groups in both countries. Their concern is the high Andean zone, where glaciers and frozen-ground systems feed the rivers below.

Researchers warn that in arid Andean valleys these ice reserves can supply more than half of river flow during the long drought. Mining infrastructure, they say, threatens exactly those systems.

Critics also point to asymmetry in oversight. In Chile, environmental monitoring sits with the national government, while in Argentina it falls to the provinces.

Argentina’s recent reform of its glacier protection law is being challenged in federal courts. Opponents argue it lets provinces strip glaciers from the national inventory and open them to mining.

What it means for foreigners and investors

For mining investors, the message from Santiago is that both governments now want the same thing. Kast, in office since March, and Javier Milei both court private capital for the sector.

The wider guest list matters as much as the bilateral track. Bolivia and Ecuador joined the common-agenda panel, and the lithium triangle Argentina shares with Chile and Bolivia ran through the discussions.

Financing panels at the summit underlined the practical bottleneck. The Inter-American Development Bank, Santander, Trafigura and the International Finance Corporation all discussed dollar credit for mid-sized miners.

The honest caveat came from Chile’s vice minister of mining, Álvaro González. He told Reuters there is no fixed timetable for implementing any of the measures under review.

Frequently Asked Questions

This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error