Codelco said it sought to take advantage of historically low interest rates to raise $1 billion via a 10-year note at 3.175% as well another $1 billion via a 30-year note at 3.958%. The issues were 2.8-times oversubscribed.

"A favorable debt market, with base rates at historically low levels, makes it attractive to pre-finance the cash needs  for 2021," said Codelco VP administration and finance Alejandro Rivera.

Through bond issues, Codelco is seeking to align its debt amortization profile with the production period of the "structural projects" the raises will finance. The projects include Chuquicamata underground, a new mine level at El Teniente, Rajo Inca and a project at Andina, many of which will be cornerstone operations for the next 50 years for the world's largest copper producer.

The bond issues take the company's debt level to some $20 billion and follows a $2 billion bond issue in September 2019.

Executive president Octavio Araneda, is seeking to slash $8 billion from the $39 billion of investment projects on the company has on the drawing table so that its debt load does not balloon out of control.

Codelco is unlikely to count with significant financial support in the near term from its owner, the Chilean state, either. Chile's government ruled out fresh funds for Codelco, as it plans to spend $3 billion this year to contain a wave of nationwide protests which rocked the country in late 2019, seeking greater equality and investment in social spending.

"We're not talking about a capital injection. The state has always supported Codelco in such a way that it can access financing via capitalisation or international markets," finance minister Ignacio Briones said during an interview with Radio Pauta Bloomberg.