The ban went into effect last month when the Interior Secretary declared polar bears are a threatened species. A pro-hunting group called the Safari Club says it plans to sue to overturn the ban. The group claims money from imported hides taken from healthy populations in Canada helps support research and conservation.
A polar bear hunt can cost $50,000.
A 1972 U.S. law banned trophy hunting of Alaskan polar bears but Congress later made an exception for hides brought in from Canada.
