EPA Administrator Lisa P. Jackson is stepping down from her position next month, setting up a likely confirmation battle next year over the Obama administration’s directions on a variety of high-profile issues, such as climate change and alternative energy strategies.

“I will leave the EPA confident the ship is sailing in the right direction, and ready in my own life for new challenges, time with my family and new opportunities to make a difference,” Jackson said in a statement released Thursday.

President Barack Obama issued a statement praising Jackson’s tenure. “Lisa has been an important part of my team, and I want to thank her for her service in my Administration and her tireless efforts to benefit the American people,” he said.

Jackson’s tenure has been consequential; environmental groups cheered her efforts, including new fuel economy standards, restrictions on soot, mercury and other toxic emissions, and the EPA’s finding that climate change poses a threat to health and the environment.

But those actions made her a top target of the GOP and some Democrats, particularly lawmakers from coal states who chafed at new regulations on coal power plants.

And one of the EPA’s toughest critics, Senate Environment and Public Works ranking member James M. Inhofe, R-Okla., issued a statement praising Jackson as a good, honest public servant, even while taking a swipe at the agency itself.

“Lisa Jackson and I disagreed on many issues and regulations while she headed the EPA, however, I have always appreciated her receptivity to my concerns, her accessibility and her honesty. She was one of the few at the EPA that was honest with me.”

And Jackson didn’t always get her way. The White House shelved the EPA’s plans for tough new standards on ozone — the main ingredient in smog — in 2011 as Obama was gearing up for re-election.