Chile's copper output will rise nearly 4 percent to more than 6 million metric tons in 2014 due to new investment and higher production at privately controlled mines.

Chile is the world's top copper producer but has been troubled by falling ore grades and aging mines. The Codelco state-owned mining company has embarked on a multibillion-dollar investment plan to improve output.

SONAMI mining association president Alberto Salas said Wednesday that Chile's copper production reached 5.77 million metric tons in 2013 and will rise to 6 million this year. He said Chile would export some $45 billion worth of copper in 2014.

Copper accounts for about a third of government revenue, and the state has a policy of shoring up national reserves during periods of high prices.