Two US airlines have announced bans on passengers from travelling with big game hunting trophies, including elephant tusks and skins from leopards or lions.
Delta and American Airlines said the embargoes will come into effect immediately amid the international uproar over the illegal killing of Cecil, a 13-year-old male African lion, by an American recreational hunter in Zimbabwe.
"Effectively immediately, Delta will officially ban shipment of all lion, leopard, elephant, rhinoceros and buffalo trophies worldwide as freight," Delta said in a statement on 3 August.
"Delta will also review acceptance policies of other hunting trophies with appropriate government agencies and other organisations supporting legal shipments."
Delta serves a number of destinations in Africa and had been subject to pressure from animal rights advocates to ban the transport of wildlife trophies.
American Airlines followed up with a similar embargo late on 3 August, even though it does not offer flights to Africa.
However, those defending big game hunting claim such bans encourage illegal poaching of wildlife.
"These embargoes were put in place as a response to pressure from anti-hunting extremists, under the false pretence that they would curb poaching and the illegal trade of restricted wildlife," the US National Rifle Association lobby group said last month after South African Airways lifted its embargo on the transport of hunting trophies.
"Ironically, embargoes like these actually increase poaching, as the revenue generated from legal hunting funds the vast majority of anti-poaching efforts."
Walter Palmer, an American dentist and recreational hunter from Minnesota, illegally shot and killed Cecil on 1 July after reportedly paying $50,000 (£32,000, €46,000) to hunt the animal.
Zimbabwean authorities are seeking the extradition of Palmer to face criminal charges, while a US public petition to extradite the American exceeded 100,000 signatures last week.