Mining giant Glencore plans to invest $1.5-billion on an expansion project at its Antapaccay mine in Peru, up from $590-million announced previously, a company executive said, in a bid to unlock the stalled plan key to maintaining copper output.

Carlos Cotera, GM of Antapaccay Mining Co, told Reuters the Glencore unit was pushing forward the "Coroccohuayco" project, which aims to extend the mine's lifespan by decades. In recent years, production has been stalled as the quality of ore grades declined.

"The Coroccohuayco project means expanding the life of the mine until at least 2045 or 2050, that's our forecast," Cotera said on Monday evening on the sidelines of a mining forum in Lima. "We estimate the investment will exceed $1.5-billion."

The electric car revolution has sharply boosted forecasts for global copper demand in the coming years with many analysts expecting a supply deficit after production and investment has slowed in key regions. Peru is the world's No. 2 copper producer, with neighbor Chile No. 1.

Cotera said annual production at Antapaccay, one of Peru's largest copper mines, has fallen steadily from 221,000 tonnes in 2016 to around 150 000 t now, making the expansion project important.

"We are confident that for at least the first 10 years of Coroccohuayco's operation copper production will be around 250,000 tonnes of copper per year," Cotera said.

The project has been delayed by social unrest in the province where the mine is located. In September 2022, residents of Espinar opposing the expansion project blocked part of an Andes mining corridor for a few days.

Antapaccay said at that time the plan was "under review." The corridor was also blocked during recent unrest following former President Pedro Castillo's ouster.

Cotera said the firm is now examining Coroccohuayco's "pre-feasibility study" and expects approval in the second half of 2024 before moving to a full feasibility study.