Chile has approved the long-awaited Puerto Exterior expansion at the Port of San Antonio, paving the way for what is being described as the largest port infrastructure project in the country’s history and a major new gateway for South American container trade.

The Valparaíso regional environmental commission unanimously approved the project’s environmental qualification resolution this week following a six-year review process that included multiple public consultations, technical amendments and indigenous consultations.

The $4.45bn public-private development will dramatically expand the capabilities of Port of San Antonio, Chile’s largest port, allowing it to handle the world’s biggest containerships while tripling cargo transfer capacity.

The project includes construction of a nearly 4 km breakwater, extensive dredging works and two semi-automated terminals each spanning around 1,730 m. Once fully operational, the new port is expected to handle up to 6m teu annually and accommodate up to eight 400 m-long containerships simultaneously.

Puerto San Antonio said the first phase, featuring an 865 m berth with capacity for 1.5m teu annually, is scheduled to begin operations around 2036.

The development comes amid intensifying competition along South America’s Pacific coast following China-backed investment in Peru’s Chancay deepwater port.