A federal appeals court is delaying its consideration of a lawsuit against the Obama administration’s smog rule to let the Trump administration decide whether it supports the regulation.

The Court of Appeals for the District of Columbia ordered the lawsuit over the Environmental Protection Agency’s (EPA) 2015 ozone pollution rule, to be paused late Tuesday.

Trump administration attorneys asked for the pause Friday evening, saying the EPA is in the process of deciding whether it wants to try to repeal the rule, defend it in court or take some other action on it.

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“EPA intends to closely review the 2015 rule, and the prior positions taken by the agency with respect to the 2015 rule may not necessarily reflect its ultimate conclusions after that review is complete,” Justice Department attorneys told the court.

Environmental groups who support the rule asked the court to deny the administration’s request earlier Tuesday, saying there are important legal issues that need quick attention by the court.

The rule set the standard allowable ozone concentration in the air at 70 parts per billion, down from the previous 75 parts per billion set in 2008.

Ozone is a byproduct of pollutants emitted by fossil fuel burning, and is linked to respiratory ailments such as asthma attacks. It is a component of smog.

A coalition of business and energy groups, along with conservative states, sued the EPA in 2015 to have the rule overturned. The Obama administration had been defending the rule against the challenge.

The court asked in its late Tuesday order that the administration file updates every 90 days on the EPA’s review of the rule.

The Trump administration has not formally said how it feels about the ozone rule. President Trump recently directed the EPA to begin repealing numerous major Obama administration rules and look for other ones that limit domestic energy production and use, but the ozone standard was not specifically mentioned.