SAN FRANCISCO (AP) — A federal judge says the Trump administration violated federal law when it failed to meet a deadline to identify all parts of the U.S. with dangerous smog levels.

U.S. District Judge Haywood Gilliam on Monday ordered the U.S. Environmental Protection Agency to complete the designations by the end of April.

His ruling was for two lawsuits, including one filed by California, thirteen other states and the District of Columbia.

The agency had until October 1, 2017 to designate what parts of the country were in and out of compliance with smog standards adopted during the Obama administration.

The designations trigger a process that forces polluted regions to take steps to improve air quality.

An email seeking comment sent to the U.S. Department of Justice was not immediately returned.