"This arbitration procedure will not affect our current operations. The amounts discussed have been paid, under protest, and are promptly related to past activities. Currently, we operate under a new contract for guarantees and investment promotion measures," said Cerro Verde in a statement.

The dispute with tax agency Sunat relates to a 1998 tax stability agreement the company signed with the government and a long history of disputed taxation amounts originating with the 2006-2008 period.

At the end of 2019, the company paid 711.1 million soles (US$214.4 million) under protest for royalties in this period.