The US government took steps on Monday to protect lions in Africa from American big-game trophy hunters by listing two lion subspecies under the Endangered Species Act. In response to the dramatic decline of lion populations in the wild, Panthera leo lions, located in western and central Africa and India, will be listed as endangered, and Panthera leo melanochaita lions, located in eastern and southern Africa, will be listed as threatened, the US Fish and Wildlife Service announced in a news release.

The steps were taken five months after the notorious killing of "Cecil," a star lion that was a tourist attraction in Hwange National Park of Zimbabwe, by Walter Palmer, a US dentist in the state of Minnesota.

The killing sparked widespread anger and protests at big-game trophy hunting in Africa, though Palmer was cleared of wrongdoing by Zimbabwean authorities who said he did not break the law.