Connecticut has joined 21 other states and seven local governments this week in filing a lawsuit to block a Trump administration plan to ease carbon pollution limits at fossil-fuel-based power plants.

The petition challenges Trump’s Affordable Clean Energy, or ACE, rule, which replaces the Obama administration’s Clean Power Plan. Opponents of the new directive have labeled it the “Dirty Power Rule,” which they say rejects the science behind climate change and prolongs reliance on coal-fired power plants.

“I believe in science. Climate change is real and if we do nothing to curb our reliance on fossil fuels we are dooming future generations and our planet,” Tong said Tuesday. “The Dirty Power rule is a craven, political attempt to protect Trump’s toxic allies in the fossil-fuel industry from the change we all know is urgently required. Trump and his Big Pollution friends need to stop prolonging this inevitable shift, and start truly investing in clean, renewable and affordable power.”

The states’ lawsuit 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.

Among those joining Connecticut in filing suit are New York, Rhode Island, Vermont, Massachusetts, Pennsylvania and New Jersey, along with the cities of Boulder, Colorado; Los Angeles; New York; Chicago; South Miami, Florida; and Philadelphia. They say the Trump administration rule violates the federal Clean Air Act by weakening pollution standards.

The Connecticut Attorney General’s Office noted that the Trump Administration rule “barely mentions climate change, much less recognize the threat it poses to people’s health, the economy and the environment.” The ACE rule also “turns a blind eye” to emissions-reduction programs, Tong’s office stated.

In issuing the ACE 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.

Tong offered a chart representing the EPA-estimated differences in benefits offered by the ACE versus the Clean Power Plan, focusing on the amount of pollutants that would be reduced by the year 2030 under each plan. The Clean Power Plan projects reductions of about 40 times what the ACE Rule would accomplish.

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.

Tong’s office noted that the implications of ACE Rule are extensive, with the International Energy Agency estimating climate change pollution from the U.S. power sector must be reduced 74 percent from 2005 by 2030 to achieve the goal of limiting the worldwide temperature increase to less than 2 degrees Celsius.

Democratic states have turned to the courts during the Trump administration to stop other attempts to ease environmental regulations established by President Barack 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.

Mike Scarcella of the New York Law Journal contributed to this story.