An exceptional authorization given by Brazil's environmental watchdog Ibama is the first step toward reverting a full curtailment of activities at the alumina refinery announced last week.
Panama could face a US$100bn arbitration claim if courts fail to uphold a contract allowing development of First Quantum Minerals' US$6.3bn Cobre Panamá project, according to local subsidiary Minera Panamá.
The country's nuclear energy commission said that it did not receive sufficient information from the company to be able to approve the requested increase.
However, the Brazilian steelmaker is still struggling with heavy indebtedness.
Companies active in Guyana, Mexico and Ecuador release exploration updates.