WASHINGTON - Wyoming lawmakers are going to have to compromise in order for wolves to be taken off the endangered species list, U.S. Fish and Wildlife Service Director Steve Williams said Thursday.

"I don't know where they are going to go," Williams said. "We are anxious to talk with them about that. We're anxious to move the process along, but the ball is really in their court. Right now I am not sure what route or avenue Wyoming wants to take."

On Wednesday, Williams helped roll out a plan to give Idaho and Montana officials more authority to manage wolves. The plan was presented after the Fish and Wildlife Service accepted Idaho and Montana's wolf management plans, but rejected Wyoming's wolf management plan.

Once all three states have acceptable plans, the process of taking the wolf off the endangered species list and fully handing management over to the states can take place.

"The next step?" Williams responded when asked what the next step for his agency is. "Well that's a question you need to ask Wyoming."

Wyoming has threatened to file a lawsuit against the Fish and Wildlife Service alleging the agency acted illegally by rejecting a ruling based on the best possible science.

Williams spent several days in Wyoming working with state legislators to craft a plan that the Fish and Wildlife Service could accept. The Legislature did not pass any of several bills about wolf management. He said he is willing to head West and work with Wyoming lawmakers again.

He stressed that for a plan to win his agency's approval, it cannot include a provision that permits certain wolves in the state to be killed without any limitations. Under Wyoming's current plan, wolves in certain areas of the state would be classified as predators and could be killed without any limits.

"The stumbling block is unregulated take," Williams said. "Call them what you want. The predator class in Wyoming is unregulated take. The Endangered Species Act says you have to have adequate regulatory mechanisms. To approve a plan that does not conform with the law doesn't make any sense."