Updated

Chile's state-run copper giant Codelco says its profit halved in 2013 from the previous year due to dwindling ore grades and tumbling prices for the red metal.

The world's largest copper company said Friday it earned $3.9 billion before taxes and extraordinary items.

Codelco's production fell by 1.5 percent in the same period to 1.62 million metric tons due to output drops in some of its key mines. Total output rose 2 percent to 1.79 million metric tons when including Codelco's shares in the Anglo Sur and El Abro deposits.

The company has been hit by rising energy costs and is pressed to dig new deposits amid falling ore grades. Codelco is struggling to finance an ambitious $30 billion investment program to boost production.