OREANDA-NEWS. March 30, 2017. The US Environmental Protection Agency (EPA) is asking a federal court to delay a ruling in litigation over the Clean Power Plan, kicking off a new legal battle over the carbon-cutting regulation.

The agency late yesterday asked the DC Circuit Court of Appeals to put the case on hold while it conducts a review of the Clean Power Plan that could lead to a change or repeal of the regulations. EPA filed the motion just hours after President Donald Trump signed an executive order directing the agency to reevaluate the Clean Power Plan and a companion rule setting CO2 limits for new coal-fired power plants.

EPA said a delay is warranted in part because any ruling by the DC Circuit is likely to be appealed to the US Supreme Court, which would require the agency to take positions on key issues before it has completed its review.

"This could call into question the fairness and integrity of the ongoing administrative process," the agency said in its court filing.

EPA asked the court to place the case in abeyance until 30 days after the conclusion of its review and any subsequent rulemaking to revise or rescind the regulations.

Supporters of the Clean Power Plan say they will oppose EPA's request. It is unusual for a case to last this long and then for a party to step back and say "we do not want a decision after all," New York attorney general Schneiderman (D) said.

"This case is fully litigated," he said. "We would seek a decision. That would be the first step."

Schneiderman is leading a coalition of 16 states and the District of Columbia that has defended the regulations in court.

The DC Circuit heard oral arguments last fall but has yet to issue a ruling in the case, which began in October 2015. The US Supreme Court put the regulation on hold last year pending the outcome of the litigation.

Environmental groups also said they will oppose the EPA motion on the same grounds. The Environmental Defense Fund called the agency's request an "outrageous attempt to prevent the DC Circuit" from issuing a ruling.

The Clean Power Plan requires states to develop plans to reduce CO2 emissions from existing power plants from 2022-2030. The agency under former president Barack Obama said the regulation offered states flexibility to decide how to meet their targets, including by using emissions trading.