The African lion—thousands of miles away but beloved by Americans—might become protected under U.S. law, the U.S. Fish and Wildlife Service announced Monday.

The proposed new rule would list lions as threatened under the Endangered Species Act. If approved, the law would make it illegal to kill or hunt captive lions in the U.S. without a permit or for a U.S. citizen to sell lions or lion parts across state or international borders. The sale of lions or lion parts within a U.S. state will remain under state jurisdiction.

Even if lions are listed as threatened, U.S. hunters could still import lions that they had killed in Africa as trophies—as long as they get permits from countries with a "scientifically