The Environmental Protection Agency isn’t saying which areas of the country are not complying with the Obama administration’s 2015 national air quality standards for smog-forming ozone just yet.

“The ozone designation process is complex and requires ongoing and extensive conversations with state and local agencies,” said EPA administrator Scott Pruitt. “As we move forward, the agency will be able to prioritize, be more responsive to local needs, and move forward on a case-by-case basis.”