About 44 miners would be impacted and the personnel reductions were effective immediately, it said in a statement.

"The continued deterioration of both the domestic and export metallurgical coal markets, driven in large part by the Covid-19 pandemic have led us to make this difficult decision," said executive chairperson Randall Atkins.

The miner remained committed to the completion of its Berwind slope development to full capacity and would restart full development and production at the mine once the markets stabilised.

"We believe that ultimately the Berwind mine will be amongst the lowest cost, high-quality low volatile coal in the Central Appalachian region," added CEO and president Michael Bauersachs in the statement.

The Berwind mine would continue to run at a reduced rate to service existing customer commitments.

On April 1, Ramaco implemented a two-week operational furlough of the majority of employees at the Elk Creek mining complex in West Virginia, which it said, at the time, was "out of an abundance of caution". It has subsequently recalled that entire workforce.