Embattled mining giant Glencore said it has started the sales process for two of its copper mines in Australia and Chile.

The firm’s Australian copper mine in Cobar, New South Wales, and its Lomas Bayas copper mine in the Atacama desert in Chile are for sale.

Glencore is attempting to reduce $30bn (£19.5bn) of debt created by its 2013 takeover of Xstrata.

Its Hong Kong-listed shares have also fallen some 55% this year.

Trading of the firm’s Hong Kong-listed shares were halted earlier on Monday ahead of the announcement.

“The sale process is in response to Glencore receiving a number of unsolicited expressions of interest for these mines from various potential buyers,” the firm said in an email.

“This will allow potential buyers to bid to purchase either one or both of the mines and may or may not result in a sale,” it added.

The Cobar operation is a high-grade underground mine and plant, while the Lomas Bayas operation is a low-cost, open pit mine.

In Australia, Glencore has 19 mining complexes across the country, including coal, copper, nickel and zinc operations, port facilities, offices and agricultural businesses, among others. It is one of the biggest exporters of Australian grain.

In Chile, Glencore owns and has stakes in several mines, as well as a hydro-power project.

Last week, the firm announced it would dramatically cut its zinc production.

The move comes amid a 30% fall in the price of zinc in recent months. The company said it would cut 500,000 tonnes of zinc production – or 4% of the world’s total supply.

Most of the zinc-related cutbacks will be in Australia, where more than 500 jobs will be lost, as well as South America and Kazakhstan.

As it attempts to reduce its debt, the firm has also cut copper production and suspended dividend payments to shareholders. It is also issuing new shares to raise money.