SANTIAGO (Reuters) -Chile's Codelco, the world's largest copper producer, on Friday lowered its 2025 production guidance following an accident at its flagship El Teniente mine, and reported lower pre-tax profit in the first half of the year.

The state-run miner now expects 2025 production of 1.34-1.37 million metric tons of copper, down from a March estimate of 1.37-1.40 million tons.

Codelco's output hit a quarter-century low in 2023, and the company has been struggling to compensate for aging deposits and delays in major expansion projects.

The accident on July 31 at El Teniente, Codelco's most profitable mine, marked a new blow, forcing mining activity and smelting to go offline for several days and causing a loss of 33,000 metric tons of copper, equivalent to $340 million.

Codelco on Friday flagged the possibility of further delays at the mine, saying sectors still in ramp-up "need to be revised" after the accident, which hit the new Andesita unit.

The accident also prompted the company to postpone its announcement of financial results for the first half of the year, originally scheduled for Aug. 1.

Between January and June, Codelco recorded pre-tax profit of $429 million, down 34% from the $653 million reported in the same period last year.

The state-owned miner said its own output totaled 634,000 metric tons, up 9% from the same period last year.