The landmark ruling by the Supreme Court to curb the EPA's powers to force a reduction in carbon emissions from coal and gas-fired power stations is seen as a major setback to President Joe Biden's climate policies.

Biden termed the Court's ruling "another devastating decision that aims to take our country backwards".

The NMA, whose members include over 250 firms involved in the mining and supply industry including coal producers, welcomed the Court's ruling.

"We are pleased to see the Court confirm that there are limits to the authority that administrative agencies have to unilaterally issue transformative rules, particularly those that impose deep and uneven economic impacts on every state and industry across the country," the Washington-based NMA said.

"Climate change is real and must be addressed, but not by running roughshod over the boundaries established around delegated powers," it said.

The case against the EPA was brought to the Court by West Virginia - a major coal producing state -  and 18 other mostly Republican states and some of the country's largest coal firms.

The Court in a 6-3 ruling on June 30 determined that Congress had not "intended to delegate…decision[s] of such economic and political significance" to the EPA.

The EPA promulgated the Clean Power Plan rule in 2015 to address carbon dioxide emissions from existing coal and natural gas-fired power plants, based on authority given to it under the 1970 Clean Air Act.

West Virginia and other states contested that decision making powers on power plants lay with states. West Virginia is second only to Wyoming as the country's largest coal producer.

The EPA said it was "deeply disappointed" by the Court's "disheartening" decision and that it was "committed to using the full scope of EPA's authorities to protect communities and reduce the pollution that is driving climate change."

Biden still may take action to reduce emissions despite the ruling.

"While this decision risks damaging our nation's ability to keep our air clean and combat climate change, I will not relent in using my lawful authorities to protect public health and tackle the climate crisis," Biden said. "Today's decision sides with special interests that have waged a long-term campaign to strip away our right to breath clean air."

Biden has directed his legal team to work with the Department of Justice and affected agencies to review the decision.

"I will take action. My administration will continue using lawful executive authority, including the EPA's legally-upheld authorities to keep our air clean, protect public health and tackle the climate crisis."

But this will be dependent on Congress and politics.

"We expect that setting specific regulatory requirements will be much more difficult to get through Congress, where Democrats have a very thin majority in the Senate," said analysts at RBC Capital Markets in New York.