A conservation group and an Arizona congressman have filed what they say is the first federal lawsuit against the proposed border wall.
The lawsuit was filed Wednesday in Tucson by the Center for Biological Diversity and U.S. Rep. Raul Grijalva, a southern Arizona Democrat.
Wildlife conservationists say the wall would be detrimental to rare animals such as jaguars and ocelots that are known to traverse the international line.
The lawsuit seeks to require the U.S. Department of Homeland Security to put together a report on construction of the wall and the environmental impact of expanded operations on the U.S.-Mexico border.
President Donald Trump has promised to build the wall and make Mexico pay for it, though Mexico has refused.