New York State Attorney General Barbara Underwood on Tuesday promised to sue the Trump administration if a proposal to roll back an Obama-era regulation reducing emissions from fossil fuel-burning power plants is adopted.

The Environmental Protection Agency announced a proposal to replace the Clean Power Plan, which was adopted by the Obama administration in 2015. That plan aims to curb fossil fuel emissions from energy plants by about a third by 2030.

The replacement rule proposed Tuesday, called the Affordable Clean Energy Rule, would give more power to states to decide how they wanted to regulate fossil-fuel emissions within their borders.

Underwood said in a statement that the state will challenge the rule if it's adopted based on the risks associated with climate change.

“'Climate change is real, no matter how much this administration tries to deny it,” Underwood said. “We need strong, immediate action to drastically cut climate change pollution and promote affordable, clean, and sustainable energy—not foot dragging and backtracking that seeks to prop up dirty, expensive power plants. “If the Trump administration's proposal to dismantle the Clean Power Plan is adopted, we will work with our state and local partners to file suit to block it—in order to protect New Yorkers, and all Americans, from the increasingly devastating impacts of climate change,” she continued.

Underwood previously led a coalition of states and municipalities in comments to the EPA opposing a repeal of the Clean Power Plan in April.

Her office is already involved in several lawsuits against the EPA over efforts to loosen or roll back Obama-era regulations. In June, it sued the agency for throwing out limits on certain greenhouse gases used in refrigeration and air conditioning.

The EPA is accepting comments on Tuesday's proposal over the next two months before the rule is finalized.