Peabody Energy, the largest private coal company in the world, may soon file for bankruptcy, citing falling global demand and "substantial doubt" about its future.
The company has been hit hard by a glut in cheap natural gas and the Obama administration's tougher, climate change-minded government. Several major coal companies have already succumbed to the changes, including Arch Coal, the second largest supplier in America.
"These projections and certain liquidity risks raise substantial doubt about whether we will meet our obligations," Peabody said in a filing to the Securities and Exchange Commission. "There exists substantial doubt whether we will be able to continue."
Shares in the company fell more than 45 percent on Wednesday after the filing.
Coal has long been lambasted for being a fuel of the past as growing concerns about climate change have led to harsh crackdowns on future mining operations. President Barack Obama halted new coal leases on public lands earlier this year. And China, by far the largest burner of coal on the planet, has promised to tackle it's gargantuan greenhouse gas emissions by 2030.
Several leading environmental groups, including 350.org, Greenpeace and WildEarth Guardians, called on Peabody to end its coal business, citing the announcement as an "opportunity to protect the climate" in a press release.
“All we’re doing is calling on the company to get on board with helping our nation and our communities transition away from coal by winding down their operations in an orderly and effective manner," Diana Best, Greenpeace's senior coal campaigner, said in the statement.
Peabody has laid off hundreds of employees over the past few years and announced in January it would pay $75 million into a health fund for thousands of retired coal workers from a now-defunct company it spun off in 2007.
The company had $6.3 billion in debt and a net loss of more than $2 billion at the end of 2015.