Gov. Nikki Haley says the federal government has agreed to remove some of the plutonium being stored in South Carolina.

Haley's office tells The Associated Press that U.S. Energy Secretary Ernest Moniz told her during a call Tuesday night 6 metric tons of plutonium currently at the Savannah River Site will ultimately be stored at a facility in New Mexico that should be operational by the end of this year.

Haley has for years spoken out against the storage of plutonium at the South Carolina complex, writing to Moniz last month saying he must stop or reroute another shipment on its way from Japan. Calling the deal a win, she also pointed out her continuing lawsuit against the Department of Energy over an unfinished project to process weapons grade plutonium also stored at the site into commercial reactor fuel.

"We will continue to watch this process carefully, as the Department of Energy has not lived up to promises made in the past," Haley said in a statement provided to AP. "We will not back down from our lawsuit until the DOE pays the $1 million a day fine they are required to under federal law."

Energy officials didn't immediately return a message seeking comment.

Tons of plutonium have accumulated over the years at the former nuclear weapons complex along the state's border with Georgia. Separate from the materials covered in Tuesday's conversation is about 7 tons of weapons grade plutonium, which is also at the site and ultimately intended to be processed into commercial nuclear reactor fuel, as part of a nonproliferation agreement with Russia.

The facility for that process is billions over budget and remains incomplete. South Carolina is already suing the federal government over what the governor has called its broken promise to the state to finish the mixed-oxide fuel facility, seeking fines of $1 million a day because the plant wasn't operational by a Jan. 1 deadline.

The Obama administration has gradually scaled down funding for the project, proposing to mothball it in 2014, citing cost overruns and delays. That prompted an earlier lawsuit, with the state saying the federal government had made a commitment to South Carolina and couldn't use money intended to build the plant to shut it down.

The state ultimately dropped the suit when the administration committed to funding the project through that fiscal year. But the administration has since said it's searching for a less expensive way to dispose of the plutonium, like immobilizing it in glass or processing it in different kinds of reactors.