WASHINGTON — The Supreme Court dealt a surprising setback to President Barack Obama on Tuesday by putting his climate change policy on hold while a coalition of coal producers and Republican-led states challenges its legality.

The justices, by a 5-4 vote, issued an unusual emergency order that blocks the Environmental Protection Agency from moving forward with its effort to reduce carbon pollution from power plants by 32 percent by 2030.

The order said the EPA's “carbon pollution emission guidelines” for power plants are “stayed pending” a decision from the U.S. Court of Appeals for the District of Columbia Circuit, which will hear the case this summer.

It is rare for the high court to intervene in a case pending in the lower courts. The brief order suggests that most of the justices have doubts about the legality of the EPA's policy.

In a separate case this term, the court will decide whether Obama went too far in issuing an executive action to defer deportation of more than 4 million immigrants here illegally.

Chief Justice John Roberts and Justices Antonin Scalia, Anthony Kennedy, Clarence Thomas and Samuel Alito joined in support.

A former Justice Department attorney who has worked on environmental litigation called the order significant.

It is “extraordinary and fairly surprising,” Washington lawyer James Rubin said. “The court essentially reviewed the merits before the D.C. Circuit even had a chance to rule on them, something the court has not done before in the context of rule-making challenge.”

The EPA regulations, known as the Clean Power Plan, would set state-by-state targets for reducing greenhouse gases from power plants.

dsavage@tribune.com