Online auctioneer eBay on Tuesday sided with conservationists by banning international sales of ivory.
"It’s the right thing to do," said eBay vice president of policy management Matt Halprin.
People trying to sell ivory products without crossing international borders must prove the offers conform to local laws, according to eBay spokeswoman Nichola Sharpe.
The restrictions take force by the end of this month.
"What we are doing now is strengthening our ivory policy to ban all cross-border trade and provide clarity to those who wish to buy or sell ivory on eBay sites," Halprin said.
By the end of June, eBay sellers will be allowed to list only ivory products for sale in their own country.
The company said it will take down listings of ivory products that offer international shipping.
"The fundamental principle of eBay is that it is a marketplace where consumers can buy and sell almost anything," Halprin said.
"However, there are instances where our policies go above and beyond upholding existing domestic or international regulations. This is the case with ivory."
The announcement comes as environmental and animal protection groups intensify pressure to eradicate illegal traffic in endangered species from the Internet.
Conservation groups have denounced eBay for not enforcing its own rules forbidding the sale of wildlife products made from protected species.
The IFAW has criticized eBay, saying banned products from species listed as facing extinction are commonly offered for sale at the website.
"This is a great improvement, we really appreciate this step," said a participant at the 171-nation Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES), meeting in The Hague.
"It is a difficult problem; they will need help with enforcement."
EBay posts rules banning the sale of endangered species or wildlife products, but says that it cannot monitor all the items posted.
EBay said that it will continue to work with law enforcement authorities and groups such as the International Fund for Animal Welfare (IFAW) and World Wildlife Fund to keep online auctions of ivory products legal.
Ivory certified as antique is exempted from a general ban on the sale of ivory, and is often used as a cover for illegal sales, experts said at the gathering in The Hague.
The new rule is intended to give international uniformity to eBay policy regarding ivory sales and supplant eBay’s policy of simply adhering to local laws, according to Sharpe.
"The key thing here is we wanted to make the policy consistent," Sharpe told AFP. "EBay is trying to set the bar and hope others will follow suit."
In countries where activists have approached eBay and other auction sites, ivory offerings have been reduced by 98 percent, according to Lynne Levine, a spokeswoman for the International Fund for Animal Welfare (IFAW).
Ismail Costa, an investigator for the French National Office for Hunting and Wildlife, said he is certain that illegal sales of endangered wildlife and wildlife products are flourishing online.
"What we see is the tip of the iceberg," Costa told AFP. "Enforcement is also very difficult. The legal mechanisms are not yet in place."