Twenty-two states including California and New York on Tuesday sued to block a Trump administration plan to roll back carbon pollution limits on fossil fuel-dependent power plants.

The petition asks the U.S. Court of Appeals for the D.C. Circuit to review the U.S. Environmental Protection Agency’s plan, published in the Federal Register in July, to repeal the Obama-era Clean Power Plan and replace it with what critics contend is a more business-friendly proposal.

The challengers include Connecticut, Pennsylvania, New Jersey and six cities. They allege the Trump administration rule violates the federal Clean Air Act by weakening pollution standards, restricting the EPA’s regulatory authority and barring states from participating in cap-and-trade programs.

The Affordable Clean Energy rule will “keep the oldest and dirtiest of coal plants in the country on life support,” Mary Nichols, chair of the California Air Resources Board, said at a press conference in Sacramento on Tuesday.

In issuing the rule in June, the EPA called the 2015 Clean Power Plan “overreaching” and said the new proposal “restores the rule of law and empowers states to continue to reduce emissions while providing affordable and reliable energy for all Americans.”

Andrew Wheeler, the EPA administrator and a former Faegre Baker Daniels lobbyist for energy companies, said in June the Trump plan “gives states the regulatory certainty they need to continue to reduce emissions.”

But critics say Trump’s rule threatens regional pacts on reducing carbon pollution from power plants, including a 10-state program in the northeast that cut greenhouse gas emissions by half between 2015 and 2017, participants say.

New York Attorney General Letitia James called the Trump administration’s plan an “unlawful, do-nothing rule.”

“My office, and this groundbreaking coalition of states and cities from across the nation, will fight back … in order to protect our future from catastrophic climate change,” James said in a statement.

Democrat-led states have regularly turned to the courts during the Trump administration to stop attempts to ease environmental regulations established by President Obama.

In many cases, including some confronting environmental rules, the Trump administration has faced setbacks. “It turns out that unraveling Barack Obama’s environmental agenda is harder than it looks,” The Washington Post reported last year in a spotlight on regulatory cases.

Massachusetts Attorney General Maura Healey on Monday announced legal action to block U.S. Fish and Wildlife Service proposals to roll back provisions in the Endangered Species Act. Earlier this month, Becerra, James and 11 other states challenged a federal rule that would weaken penalties on carmakers that fail to meet certain fuel economy standards.