The change marks a shift in efforts to stop the importation of elephant tusks and hides, overriding a 2014 ban imposed by the Obama administration.
In an information sheet explaining why it was lifting the elephant import prohibition, the Fish and Wildlife Service noted that Zimbabwe had enacted a national elephant management plan and pointed to improvements in tracking hunting activity and "a more systematic, scientific approach to establish national quotas".
Trump tweeted that the policy had been "under study for years".
Donald Trump says he is halting a controversial change allowing the import of elephants killed by hunters overseas. He said he would put the decision "on hold" and review it with Interior Secretary Ryan Zinke.
Earlier on Friday, Press Secretary Sarah Huckabee Sanders defended Trump's original repeal of the ban, saying, "This review established that both Zambia and Zimbabwe had met new standards, strict worldwide conservation standards that allowed Americans to resume hunting in those countries".
The move was met with a barrage of criticism from animal rights groups and activists.More news: Facebook wants your nudes to combat revenge porn
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Mr Royce said that when carefully regulated, conservation hunts could help the wildlife population, but "that said, this is the wrong move at the wrong time".
On Friday, the administration put its decision on hold.
The African bush elephant is now listed as endangered under the Endangered Species Act, but a provision of the law allows for the import of trophies if it can be proved that hunting the animals contributes to conservation efforts.
African elephants' population shrank by 30% from 2007 to 2014, in large part because of poaching. Elephant populations, in particular, have been devastated across Africa over the past century.
Despite the outcry and Trump's stated reversal, the global affairs page of the US Fish and Wildlife Service still - as of Saturday morning local time - says it will issue permits for importing big game animal parts. Where 5 million of the giant pachyderms once roamed African savannahs, there are now just 400,000.
"(It's) a great travesty for elephants", Tanya Sanerib Sr., with the Attorney Center for Biological Diversity, said.